wcdma fdd mode transmitter - 140.117.160.140140.117.160.140/.../9222/bbic-1-wcdmatransmitter.pdf ·...

101
1 WCDMA FDD Mode Transmitter Dr. Chih-Peng Li (李志鵬)

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Page 1: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

1

WCDMA FDD Mode Transmitter

Dr Chih-Peng Li (李志鵬)

2

Table of ContentsTraditional Sequential ASIC Design FlowIntroduction to WCDMA Transmitter Specifications

WCDMA Network ArchitecturePhysical Layer General DescriptionMultiplexing and Channel Coding (MCC)WCDMA Uplink Physical LayerWCDMA Downlink Physical Layer

3

References

3GPP Technical Specification (Release 1999 25 Series)WCDMA for UMTS ndash Radio Access For Third Generation Mobile Communications

-- by Harri Holma and Antti Toskala Artech House 2001

Wireless Communications - Principles amp Practice-- by Theodore S Rappaport Prentice Hall 2nd Edition Dec 31 2001

4

Traditional Sequential ASIC Design Flow

5

Traditional Sequential ASIC Design FlowSpecification

System ModelsArchitecture Design

RTL Design

Logic synthesis

Physical Design

RTL Design

Functional Verification

Logical Synthesis

Timing Verification

P amp R

Physical Verification

Prototype Build amp Test Prototype

6

WCDMA Network Architecture

7

Network Elements in a WCDMA PLMNUu Iu

USIM

ME

Cu

UE

Node B

Node B

Node B

Node B

RNC

RNC

Iub Iur

UTRAN

MSCVLR GMSC

SGSN GGSN

HLR

Core Network

PLMN PSTNISDN hellip etc

Internet

ExternalNetworks

bullPLMN Public Land Mobile Network One PLMN is operated by a single operator

8

User Equipment (UE)The UE consists of two parts

The Mobile Equipment (ME) is the radio terminal used for radio communication over the Uu interfaceThe UMTS Subscriber Identity Module (USIM) is a smartcard that holds the subscriber identity performs authentication algorithms and stores authentication and encryption keys and some subscription information that is needed at the terminal

UTRAN consists of two distinct elementsThe Node B converts the data flow between the Iub and Uuinterfaces It also participates in radio resource managementThe Radio Network Controller (RNC) owns and controls the radio resources in its domain (the Node Bs connected to it) RNC is the service access point for all services UTRAN provides the core network (CN)

9

WCDMA System Architecture

UMTS system utilizes the same well-known architecture that has been used by all main 2nd generation systemsThe network elements are grouped into

The Radio Access Network (RAN UMTS Terrestrial RAN = UTRAN) that handles all radio-related functionalityThe Core Network (CN) which is responsible for switching and routing calls and data connections to external networks

Both User Equipment (UE) and UTRAN consist of completely new protocols which is based on the new WCDMA radio technologyThe definition of CN is adopted from GSM

10

Main Elements of the GSM Core Network

HLR (Home Location Register) is a database located in the userrsquos home system that stores the master copy of the userrsquos service profile

The service profile consists of for example information on allowed services forbidden roaming areas and Supplementary Service information such as status of call forwarding and the call forwarding numberIt is created when a new user subscribes to the systemHLR stores the UE location on the level of MSCVLR andor SGSN

11

MSCVLR (Mobile Services Switching Center Visitor Location Register) is the switch (MSC) and database (VLR) that serves the UE in its current location for circuit switched services

The MSC function is used to switch the CS transactionsThe VLR function holds a copy of the visiting userrsquos service profile as well as more precise information on the UErsquoslocation within the serving system

Main Elements of the GSM Core Network

12

GMSC (Gateway MSC) is the switch at the point where UMTS PLMN is connected to external CS networks

All incoming and outgoing circuit switched connections go through GMSC

SGSN (Serving GPRS (General Packet Radio Service) Support Node) functionality is similar to that of MSCVLR but is typically used for Packet Switched (PS) servicesGGSN (Gateway GPRS Support Node) functionality is close to that of GMSC but is in relation to PS services

Main Elements of the GSM Core Network

13

InterfacesCu Interface this is the electrical interface between the USIM smartcard and the ME The interface follows a standard format for smartcardsUu Interface this is the WCDMA radio interface which is the subject of the main part of WCDMA technology This is also the most important open interface in UMTSIu Interface this connects UTRAN to the CNIur Interface the open Iur interface allows soft handover between RNCs from different manufacturersIub Interface the Iub connects a Node B and an RNC UMTS is the first commercial mobile telephony system where the Controller-Base Station interface is standardized as a fully open interface

14

WCDMA Physical Layer General Description (3GPP TS 25201)

15

Elements of A Digital Communications System

Information Bits

)(ˆ tsi

Format SourceEncoding Encryption Channel

Encoding Multiplexing Modulation FrequencySpreading

MultipleAccess

TXRFPA

BitStream

DigitalWaveformSynchronization

CHANNEL

Source Bits Channel Bits

Channel BitsSource Bits

)(tsiDigitalInput

im

DigitalOutput

im

Information Sink

From Other Sources

To Other Destinations

Optional

Essential

Interleaving

Format SourceDecoding Decryption Channel

Decoding Demultiplexing Demodulation FrequencyDespreading

MultipleAccess

RXRFIF

Deinterleaving

16

Establishes the characteristics of the layer-1 transport channels and physical channels in the FDD mode and specifies

Transport channelsPhysical channels and their structureRelative timing between different physical

channels in the same link and relative timing between uplink and downlink

Mapping of transport channels onto the physical channels

Physical channels and mapping of transport channels onto physical channels (FDD)

TS 25211

Describes the contents of the layer 1 documents (TS 25200 series) where to find information a general description of layer 1

Physical Layer ndashgeneral description

TS 25201

3GPP (Radio Access Network) RAN Specifications

17

Establishes the characteristics of the spreading and modulation in the FDD mode and specifies

SpreadingGeneration of channelization and scrambling codesGeneration of random access preamble codesGeneration of synchronization codesModulation

Spreading and Modulation (FDD)

TS 25213

Describes multiplexing channel coding and interleaving in the FDD mode and specifies

Coding and multiplexing of transport channelsChannel coding alternativesCoding for layer 1 control informationDifferent interleaversRate matchingPhysical channel segmentation and mapping

Multiplexing and Channel Coding (FDD)

TS 25212

3GPP (Radio Access Network) RAN Specifications

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 2: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

2

Table of ContentsTraditional Sequential ASIC Design FlowIntroduction to WCDMA Transmitter Specifications

WCDMA Network ArchitecturePhysical Layer General DescriptionMultiplexing and Channel Coding (MCC)WCDMA Uplink Physical LayerWCDMA Downlink Physical Layer

3

References

3GPP Technical Specification (Release 1999 25 Series)WCDMA for UMTS ndash Radio Access For Third Generation Mobile Communications

-- by Harri Holma and Antti Toskala Artech House 2001

Wireless Communications - Principles amp Practice-- by Theodore S Rappaport Prentice Hall 2nd Edition Dec 31 2001

4

Traditional Sequential ASIC Design Flow

5

Traditional Sequential ASIC Design FlowSpecification

System ModelsArchitecture Design

RTL Design

Logic synthesis

Physical Design

RTL Design

Functional Verification

Logical Synthesis

Timing Verification

P amp R

Physical Verification

Prototype Build amp Test Prototype

6

WCDMA Network Architecture

7

Network Elements in a WCDMA PLMNUu Iu

USIM

ME

Cu

UE

Node B

Node B

Node B

Node B

RNC

RNC

Iub Iur

UTRAN

MSCVLR GMSC

SGSN GGSN

HLR

Core Network

PLMN PSTNISDN hellip etc

Internet

ExternalNetworks

bullPLMN Public Land Mobile Network One PLMN is operated by a single operator

8

User Equipment (UE)The UE consists of two parts

The Mobile Equipment (ME) is the radio terminal used for radio communication over the Uu interfaceThe UMTS Subscriber Identity Module (USIM) is a smartcard that holds the subscriber identity performs authentication algorithms and stores authentication and encryption keys and some subscription information that is needed at the terminal

UTRAN consists of two distinct elementsThe Node B converts the data flow between the Iub and Uuinterfaces It also participates in radio resource managementThe Radio Network Controller (RNC) owns and controls the radio resources in its domain (the Node Bs connected to it) RNC is the service access point for all services UTRAN provides the core network (CN)

9

WCDMA System Architecture

UMTS system utilizes the same well-known architecture that has been used by all main 2nd generation systemsThe network elements are grouped into

The Radio Access Network (RAN UMTS Terrestrial RAN = UTRAN) that handles all radio-related functionalityThe Core Network (CN) which is responsible for switching and routing calls and data connections to external networks

Both User Equipment (UE) and UTRAN consist of completely new protocols which is based on the new WCDMA radio technologyThe definition of CN is adopted from GSM

10

Main Elements of the GSM Core Network

HLR (Home Location Register) is a database located in the userrsquos home system that stores the master copy of the userrsquos service profile

The service profile consists of for example information on allowed services forbidden roaming areas and Supplementary Service information such as status of call forwarding and the call forwarding numberIt is created when a new user subscribes to the systemHLR stores the UE location on the level of MSCVLR andor SGSN

11

MSCVLR (Mobile Services Switching Center Visitor Location Register) is the switch (MSC) and database (VLR) that serves the UE in its current location for circuit switched services

The MSC function is used to switch the CS transactionsThe VLR function holds a copy of the visiting userrsquos service profile as well as more precise information on the UErsquoslocation within the serving system

Main Elements of the GSM Core Network

12

GMSC (Gateway MSC) is the switch at the point where UMTS PLMN is connected to external CS networks

All incoming and outgoing circuit switched connections go through GMSC

SGSN (Serving GPRS (General Packet Radio Service) Support Node) functionality is similar to that of MSCVLR but is typically used for Packet Switched (PS) servicesGGSN (Gateway GPRS Support Node) functionality is close to that of GMSC but is in relation to PS services

Main Elements of the GSM Core Network

13

InterfacesCu Interface this is the electrical interface between the USIM smartcard and the ME The interface follows a standard format for smartcardsUu Interface this is the WCDMA radio interface which is the subject of the main part of WCDMA technology This is also the most important open interface in UMTSIu Interface this connects UTRAN to the CNIur Interface the open Iur interface allows soft handover between RNCs from different manufacturersIub Interface the Iub connects a Node B and an RNC UMTS is the first commercial mobile telephony system where the Controller-Base Station interface is standardized as a fully open interface

14

WCDMA Physical Layer General Description (3GPP TS 25201)

15

Elements of A Digital Communications System

Information Bits

)(ˆ tsi

Format SourceEncoding Encryption Channel

Encoding Multiplexing Modulation FrequencySpreading

MultipleAccess

TXRFPA

BitStream

DigitalWaveformSynchronization

CHANNEL

Source Bits Channel Bits

Channel BitsSource Bits

)(tsiDigitalInput

im

DigitalOutput

im

Information Sink

From Other Sources

To Other Destinations

Optional

Essential

Interleaving

Format SourceDecoding Decryption Channel

Decoding Demultiplexing Demodulation FrequencyDespreading

MultipleAccess

RXRFIF

Deinterleaving

16

Establishes the characteristics of the layer-1 transport channels and physical channels in the FDD mode and specifies

Transport channelsPhysical channels and their structureRelative timing between different physical

channels in the same link and relative timing between uplink and downlink

Mapping of transport channels onto the physical channels

Physical channels and mapping of transport channels onto physical channels (FDD)

TS 25211

Describes the contents of the layer 1 documents (TS 25200 series) where to find information a general description of layer 1

Physical Layer ndashgeneral description

TS 25201

3GPP (Radio Access Network) RAN Specifications

17

Establishes the characteristics of the spreading and modulation in the FDD mode and specifies

SpreadingGeneration of channelization and scrambling codesGeneration of random access preamble codesGeneration of synchronization codesModulation

Spreading and Modulation (FDD)

TS 25213

Describes multiplexing channel coding and interleaving in the FDD mode and specifies

Coding and multiplexing of transport channelsChannel coding alternativesCoding for layer 1 control informationDifferent interleaversRate matchingPhysical channel segmentation and mapping

Multiplexing and Channel Coding (FDD)

TS 25212

3GPP (Radio Access Network) RAN Specifications

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 3: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

3

References

3GPP Technical Specification (Release 1999 25 Series)WCDMA for UMTS ndash Radio Access For Third Generation Mobile Communications

-- by Harri Holma and Antti Toskala Artech House 2001

Wireless Communications - Principles amp Practice-- by Theodore S Rappaport Prentice Hall 2nd Edition Dec 31 2001

4

Traditional Sequential ASIC Design Flow

5

Traditional Sequential ASIC Design FlowSpecification

System ModelsArchitecture Design

RTL Design

Logic synthesis

Physical Design

RTL Design

Functional Verification

Logical Synthesis

Timing Verification

P amp R

Physical Verification

Prototype Build amp Test Prototype

6

WCDMA Network Architecture

7

Network Elements in a WCDMA PLMNUu Iu

USIM

ME

Cu

UE

Node B

Node B

Node B

Node B

RNC

RNC

Iub Iur

UTRAN

MSCVLR GMSC

SGSN GGSN

HLR

Core Network

PLMN PSTNISDN hellip etc

Internet

ExternalNetworks

bullPLMN Public Land Mobile Network One PLMN is operated by a single operator

8

User Equipment (UE)The UE consists of two parts

The Mobile Equipment (ME) is the radio terminal used for radio communication over the Uu interfaceThe UMTS Subscriber Identity Module (USIM) is a smartcard that holds the subscriber identity performs authentication algorithms and stores authentication and encryption keys and some subscription information that is needed at the terminal

UTRAN consists of two distinct elementsThe Node B converts the data flow between the Iub and Uuinterfaces It also participates in radio resource managementThe Radio Network Controller (RNC) owns and controls the radio resources in its domain (the Node Bs connected to it) RNC is the service access point for all services UTRAN provides the core network (CN)

9

WCDMA System Architecture

UMTS system utilizes the same well-known architecture that has been used by all main 2nd generation systemsThe network elements are grouped into

The Radio Access Network (RAN UMTS Terrestrial RAN = UTRAN) that handles all radio-related functionalityThe Core Network (CN) which is responsible for switching and routing calls and data connections to external networks

Both User Equipment (UE) and UTRAN consist of completely new protocols which is based on the new WCDMA radio technologyThe definition of CN is adopted from GSM

10

Main Elements of the GSM Core Network

HLR (Home Location Register) is a database located in the userrsquos home system that stores the master copy of the userrsquos service profile

The service profile consists of for example information on allowed services forbidden roaming areas and Supplementary Service information such as status of call forwarding and the call forwarding numberIt is created when a new user subscribes to the systemHLR stores the UE location on the level of MSCVLR andor SGSN

11

MSCVLR (Mobile Services Switching Center Visitor Location Register) is the switch (MSC) and database (VLR) that serves the UE in its current location for circuit switched services

The MSC function is used to switch the CS transactionsThe VLR function holds a copy of the visiting userrsquos service profile as well as more precise information on the UErsquoslocation within the serving system

Main Elements of the GSM Core Network

12

GMSC (Gateway MSC) is the switch at the point where UMTS PLMN is connected to external CS networks

All incoming and outgoing circuit switched connections go through GMSC

SGSN (Serving GPRS (General Packet Radio Service) Support Node) functionality is similar to that of MSCVLR but is typically used for Packet Switched (PS) servicesGGSN (Gateway GPRS Support Node) functionality is close to that of GMSC but is in relation to PS services

Main Elements of the GSM Core Network

13

InterfacesCu Interface this is the electrical interface between the USIM smartcard and the ME The interface follows a standard format for smartcardsUu Interface this is the WCDMA radio interface which is the subject of the main part of WCDMA technology This is also the most important open interface in UMTSIu Interface this connects UTRAN to the CNIur Interface the open Iur interface allows soft handover between RNCs from different manufacturersIub Interface the Iub connects a Node B and an RNC UMTS is the first commercial mobile telephony system where the Controller-Base Station interface is standardized as a fully open interface

14

WCDMA Physical Layer General Description (3GPP TS 25201)

15

Elements of A Digital Communications System

Information Bits

)(ˆ tsi

Format SourceEncoding Encryption Channel

Encoding Multiplexing Modulation FrequencySpreading

MultipleAccess

TXRFPA

BitStream

DigitalWaveformSynchronization

CHANNEL

Source Bits Channel Bits

Channel BitsSource Bits

)(tsiDigitalInput

im

DigitalOutput

im

Information Sink

From Other Sources

To Other Destinations

Optional

Essential

Interleaving

Format SourceDecoding Decryption Channel

Decoding Demultiplexing Demodulation FrequencyDespreading

MultipleAccess

RXRFIF

Deinterleaving

16

Establishes the characteristics of the layer-1 transport channels and physical channels in the FDD mode and specifies

Transport channelsPhysical channels and their structureRelative timing between different physical

channels in the same link and relative timing between uplink and downlink

Mapping of transport channels onto the physical channels

Physical channels and mapping of transport channels onto physical channels (FDD)

TS 25211

Describes the contents of the layer 1 documents (TS 25200 series) where to find information a general description of layer 1

Physical Layer ndashgeneral description

TS 25201

3GPP (Radio Access Network) RAN Specifications

17

Establishes the characteristics of the spreading and modulation in the FDD mode and specifies

SpreadingGeneration of channelization and scrambling codesGeneration of random access preamble codesGeneration of synchronization codesModulation

Spreading and Modulation (FDD)

TS 25213

Describes multiplexing channel coding and interleaving in the FDD mode and specifies

Coding and multiplexing of transport channelsChannel coding alternativesCoding for layer 1 control informationDifferent interleaversRate matchingPhysical channel segmentation and mapping

Multiplexing and Channel Coding (FDD)

TS 25212

3GPP (Radio Access Network) RAN Specifications

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 4: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

4

Traditional Sequential ASIC Design Flow

5

Traditional Sequential ASIC Design FlowSpecification

System ModelsArchitecture Design

RTL Design

Logic synthesis

Physical Design

RTL Design

Functional Verification

Logical Synthesis

Timing Verification

P amp R

Physical Verification

Prototype Build amp Test Prototype

6

WCDMA Network Architecture

7

Network Elements in a WCDMA PLMNUu Iu

USIM

ME

Cu

UE

Node B

Node B

Node B

Node B

RNC

RNC

Iub Iur

UTRAN

MSCVLR GMSC

SGSN GGSN

HLR

Core Network

PLMN PSTNISDN hellip etc

Internet

ExternalNetworks

bullPLMN Public Land Mobile Network One PLMN is operated by a single operator

8

User Equipment (UE)The UE consists of two parts

The Mobile Equipment (ME) is the radio terminal used for radio communication over the Uu interfaceThe UMTS Subscriber Identity Module (USIM) is a smartcard that holds the subscriber identity performs authentication algorithms and stores authentication and encryption keys and some subscription information that is needed at the terminal

UTRAN consists of two distinct elementsThe Node B converts the data flow between the Iub and Uuinterfaces It also participates in radio resource managementThe Radio Network Controller (RNC) owns and controls the radio resources in its domain (the Node Bs connected to it) RNC is the service access point for all services UTRAN provides the core network (CN)

9

WCDMA System Architecture

UMTS system utilizes the same well-known architecture that has been used by all main 2nd generation systemsThe network elements are grouped into

The Radio Access Network (RAN UMTS Terrestrial RAN = UTRAN) that handles all radio-related functionalityThe Core Network (CN) which is responsible for switching and routing calls and data connections to external networks

Both User Equipment (UE) and UTRAN consist of completely new protocols which is based on the new WCDMA radio technologyThe definition of CN is adopted from GSM

10

Main Elements of the GSM Core Network

HLR (Home Location Register) is a database located in the userrsquos home system that stores the master copy of the userrsquos service profile

The service profile consists of for example information on allowed services forbidden roaming areas and Supplementary Service information such as status of call forwarding and the call forwarding numberIt is created when a new user subscribes to the systemHLR stores the UE location on the level of MSCVLR andor SGSN

11

MSCVLR (Mobile Services Switching Center Visitor Location Register) is the switch (MSC) and database (VLR) that serves the UE in its current location for circuit switched services

The MSC function is used to switch the CS transactionsThe VLR function holds a copy of the visiting userrsquos service profile as well as more precise information on the UErsquoslocation within the serving system

Main Elements of the GSM Core Network

12

GMSC (Gateway MSC) is the switch at the point where UMTS PLMN is connected to external CS networks

All incoming and outgoing circuit switched connections go through GMSC

SGSN (Serving GPRS (General Packet Radio Service) Support Node) functionality is similar to that of MSCVLR but is typically used for Packet Switched (PS) servicesGGSN (Gateway GPRS Support Node) functionality is close to that of GMSC but is in relation to PS services

Main Elements of the GSM Core Network

13

InterfacesCu Interface this is the electrical interface between the USIM smartcard and the ME The interface follows a standard format for smartcardsUu Interface this is the WCDMA radio interface which is the subject of the main part of WCDMA technology This is also the most important open interface in UMTSIu Interface this connects UTRAN to the CNIur Interface the open Iur interface allows soft handover between RNCs from different manufacturersIub Interface the Iub connects a Node B and an RNC UMTS is the first commercial mobile telephony system where the Controller-Base Station interface is standardized as a fully open interface

14

WCDMA Physical Layer General Description (3GPP TS 25201)

15

Elements of A Digital Communications System

Information Bits

)(ˆ tsi

Format SourceEncoding Encryption Channel

Encoding Multiplexing Modulation FrequencySpreading

MultipleAccess

TXRFPA

BitStream

DigitalWaveformSynchronization

CHANNEL

Source Bits Channel Bits

Channel BitsSource Bits

)(tsiDigitalInput

im

DigitalOutput

im

Information Sink

From Other Sources

To Other Destinations

Optional

Essential

Interleaving

Format SourceDecoding Decryption Channel

Decoding Demultiplexing Demodulation FrequencyDespreading

MultipleAccess

RXRFIF

Deinterleaving

16

Establishes the characteristics of the layer-1 transport channels and physical channels in the FDD mode and specifies

Transport channelsPhysical channels and their structureRelative timing between different physical

channels in the same link and relative timing between uplink and downlink

Mapping of transport channels onto the physical channels

Physical channels and mapping of transport channels onto physical channels (FDD)

TS 25211

Describes the contents of the layer 1 documents (TS 25200 series) where to find information a general description of layer 1

Physical Layer ndashgeneral description

TS 25201

3GPP (Radio Access Network) RAN Specifications

17

Establishes the characteristics of the spreading and modulation in the FDD mode and specifies

SpreadingGeneration of channelization and scrambling codesGeneration of random access preamble codesGeneration of synchronization codesModulation

Spreading and Modulation (FDD)

TS 25213

Describes multiplexing channel coding and interleaving in the FDD mode and specifies

Coding and multiplexing of transport channelsChannel coding alternativesCoding for layer 1 control informationDifferent interleaversRate matchingPhysical channel segmentation and mapping

Multiplexing and Channel Coding (FDD)

TS 25212

3GPP (Radio Access Network) RAN Specifications

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 5: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

5

Traditional Sequential ASIC Design FlowSpecification

System ModelsArchitecture Design

RTL Design

Logic synthesis

Physical Design

RTL Design

Functional Verification

Logical Synthesis

Timing Verification

P amp R

Physical Verification

Prototype Build amp Test Prototype

6

WCDMA Network Architecture

7

Network Elements in a WCDMA PLMNUu Iu

USIM

ME

Cu

UE

Node B

Node B

Node B

Node B

RNC

RNC

Iub Iur

UTRAN

MSCVLR GMSC

SGSN GGSN

HLR

Core Network

PLMN PSTNISDN hellip etc

Internet

ExternalNetworks

bullPLMN Public Land Mobile Network One PLMN is operated by a single operator

8

User Equipment (UE)The UE consists of two parts

The Mobile Equipment (ME) is the radio terminal used for radio communication over the Uu interfaceThe UMTS Subscriber Identity Module (USIM) is a smartcard that holds the subscriber identity performs authentication algorithms and stores authentication and encryption keys and some subscription information that is needed at the terminal

UTRAN consists of two distinct elementsThe Node B converts the data flow between the Iub and Uuinterfaces It also participates in radio resource managementThe Radio Network Controller (RNC) owns and controls the radio resources in its domain (the Node Bs connected to it) RNC is the service access point for all services UTRAN provides the core network (CN)

9

WCDMA System Architecture

UMTS system utilizes the same well-known architecture that has been used by all main 2nd generation systemsThe network elements are grouped into

The Radio Access Network (RAN UMTS Terrestrial RAN = UTRAN) that handles all radio-related functionalityThe Core Network (CN) which is responsible for switching and routing calls and data connections to external networks

Both User Equipment (UE) and UTRAN consist of completely new protocols which is based on the new WCDMA radio technologyThe definition of CN is adopted from GSM

10

Main Elements of the GSM Core Network

HLR (Home Location Register) is a database located in the userrsquos home system that stores the master copy of the userrsquos service profile

The service profile consists of for example information on allowed services forbidden roaming areas and Supplementary Service information such as status of call forwarding and the call forwarding numberIt is created when a new user subscribes to the systemHLR stores the UE location on the level of MSCVLR andor SGSN

11

MSCVLR (Mobile Services Switching Center Visitor Location Register) is the switch (MSC) and database (VLR) that serves the UE in its current location for circuit switched services

The MSC function is used to switch the CS transactionsThe VLR function holds a copy of the visiting userrsquos service profile as well as more precise information on the UErsquoslocation within the serving system

Main Elements of the GSM Core Network

12

GMSC (Gateway MSC) is the switch at the point where UMTS PLMN is connected to external CS networks

All incoming and outgoing circuit switched connections go through GMSC

SGSN (Serving GPRS (General Packet Radio Service) Support Node) functionality is similar to that of MSCVLR but is typically used for Packet Switched (PS) servicesGGSN (Gateway GPRS Support Node) functionality is close to that of GMSC but is in relation to PS services

Main Elements of the GSM Core Network

13

InterfacesCu Interface this is the electrical interface between the USIM smartcard and the ME The interface follows a standard format for smartcardsUu Interface this is the WCDMA radio interface which is the subject of the main part of WCDMA technology This is also the most important open interface in UMTSIu Interface this connects UTRAN to the CNIur Interface the open Iur interface allows soft handover between RNCs from different manufacturersIub Interface the Iub connects a Node B and an RNC UMTS is the first commercial mobile telephony system where the Controller-Base Station interface is standardized as a fully open interface

14

WCDMA Physical Layer General Description (3GPP TS 25201)

15

Elements of A Digital Communications System

Information Bits

)(ˆ tsi

Format SourceEncoding Encryption Channel

Encoding Multiplexing Modulation FrequencySpreading

MultipleAccess

TXRFPA

BitStream

DigitalWaveformSynchronization

CHANNEL

Source Bits Channel Bits

Channel BitsSource Bits

)(tsiDigitalInput

im

DigitalOutput

im

Information Sink

From Other Sources

To Other Destinations

Optional

Essential

Interleaving

Format SourceDecoding Decryption Channel

Decoding Demultiplexing Demodulation FrequencyDespreading

MultipleAccess

RXRFIF

Deinterleaving

16

Establishes the characteristics of the layer-1 transport channels and physical channels in the FDD mode and specifies

Transport channelsPhysical channels and their structureRelative timing between different physical

channels in the same link and relative timing between uplink and downlink

Mapping of transport channels onto the physical channels

Physical channels and mapping of transport channels onto physical channels (FDD)

TS 25211

Describes the contents of the layer 1 documents (TS 25200 series) where to find information a general description of layer 1

Physical Layer ndashgeneral description

TS 25201

3GPP (Radio Access Network) RAN Specifications

17

Establishes the characteristics of the spreading and modulation in the FDD mode and specifies

SpreadingGeneration of channelization and scrambling codesGeneration of random access preamble codesGeneration of synchronization codesModulation

Spreading and Modulation (FDD)

TS 25213

Describes multiplexing channel coding and interleaving in the FDD mode and specifies

Coding and multiplexing of transport channelsChannel coding alternativesCoding for layer 1 control informationDifferent interleaversRate matchingPhysical channel segmentation and mapping

Multiplexing and Channel Coding (FDD)

TS 25212

3GPP (Radio Access Network) RAN Specifications

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 6: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

6

WCDMA Network Architecture

7

Network Elements in a WCDMA PLMNUu Iu

USIM

ME

Cu

UE

Node B

Node B

Node B

Node B

RNC

RNC

Iub Iur

UTRAN

MSCVLR GMSC

SGSN GGSN

HLR

Core Network

PLMN PSTNISDN hellip etc

Internet

ExternalNetworks

bullPLMN Public Land Mobile Network One PLMN is operated by a single operator

8

User Equipment (UE)The UE consists of two parts

The Mobile Equipment (ME) is the radio terminal used for radio communication over the Uu interfaceThe UMTS Subscriber Identity Module (USIM) is a smartcard that holds the subscriber identity performs authentication algorithms and stores authentication and encryption keys and some subscription information that is needed at the terminal

UTRAN consists of two distinct elementsThe Node B converts the data flow between the Iub and Uuinterfaces It also participates in radio resource managementThe Radio Network Controller (RNC) owns and controls the radio resources in its domain (the Node Bs connected to it) RNC is the service access point for all services UTRAN provides the core network (CN)

9

WCDMA System Architecture

UMTS system utilizes the same well-known architecture that has been used by all main 2nd generation systemsThe network elements are grouped into

The Radio Access Network (RAN UMTS Terrestrial RAN = UTRAN) that handles all radio-related functionalityThe Core Network (CN) which is responsible for switching and routing calls and data connections to external networks

Both User Equipment (UE) and UTRAN consist of completely new protocols which is based on the new WCDMA radio technologyThe definition of CN is adopted from GSM

10

Main Elements of the GSM Core Network

HLR (Home Location Register) is a database located in the userrsquos home system that stores the master copy of the userrsquos service profile

The service profile consists of for example information on allowed services forbidden roaming areas and Supplementary Service information such as status of call forwarding and the call forwarding numberIt is created when a new user subscribes to the systemHLR stores the UE location on the level of MSCVLR andor SGSN

11

MSCVLR (Mobile Services Switching Center Visitor Location Register) is the switch (MSC) and database (VLR) that serves the UE in its current location for circuit switched services

The MSC function is used to switch the CS transactionsThe VLR function holds a copy of the visiting userrsquos service profile as well as more precise information on the UErsquoslocation within the serving system

Main Elements of the GSM Core Network

12

GMSC (Gateway MSC) is the switch at the point where UMTS PLMN is connected to external CS networks

All incoming and outgoing circuit switched connections go through GMSC

SGSN (Serving GPRS (General Packet Radio Service) Support Node) functionality is similar to that of MSCVLR but is typically used for Packet Switched (PS) servicesGGSN (Gateway GPRS Support Node) functionality is close to that of GMSC but is in relation to PS services

Main Elements of the GSM Core Network

13

InterfacesCu Interface this is the electrical interface between the USIM smartcard and the ME The interface follows a standard format for smartcardsUu Interface this is the WCDMA radio interface which is the subject of the main part of WCDMA technology This is also the most important open interface in UMTSIu Interface this connects UTRAN to the CNIur Interface the open Iur interface allows soft handover between RNCs from different manufacturersIub Interface the Iub connects a Node B and an RNC UMTS is the first commercial mobile telephony system where the Controller-Base Station interface is standardized as a fully open interface

14

WCDMA Physical Layer General Description (3GPP TS 25201)

15

Elements of A Digital Communications System

Information Bits

)(ˆ tsi

Format SourceEncoding Encryption Channel

Encoding Multiplexing Modulation FrequencySpreading

MultipleAccess

TXRFPA

BitStream

DigitalWaveformSynchronization

CHANNEL

Source Bits Channel Bits

Channel BitsSource Bits

)(tsiDigitalInput

im

DigitalOutput

im

Information Sink

From Other Sources

To Other Destinations

Optional

Essential

Interleaving

Format SourceDecoding Decryption Channel

Decoding Demultiplexing Demodulation FrequencyDespreading

MultipleAccess

RXRFIF

Deinterleaving

16

Establishes the characteristics of the layer-1 transport channels and physical channels in the FDD mode and specifies

Transport channelsPhysical channels and their structureRelative timing between different physical

channels in the same link and relative timing between uplink and downlink

Mapping of transport channels onto the physical channels

Physical channels and mapping of transport channels onto physical channels (FDD)

TS 25211

Describes the contents of the layer 1 documents (TS 25200 series) where to find information a general description of layer 1

Physical Layer ndashgeneral description

TS 25201

3GPP (Radio Access Network) RAN Specifications

17

Establishes the characteristics of the spreading and modulation in the FDD mode and specifies

SpreadingGeneration of channelization and scrambling codesGeneration of random access preamble codesGeneration of synchronization codesModulation

Spreading and Modulation (FDD)

TS 25213

Describes multiplexing channel coding and interleaving in the FDD mode and specifies

Coding and multiplexing of transport channelsChannel coding alternativesCoding for layer 1 control informationDifferent interleaversRate matchingPhysical channel segmentation and mapping

Multiplexing and Channel Coding (FDD)

TS 25212

3GPP (Radio Access Network) RAN Specifications

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 7: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

7

Network Elements in a WCDMA PLMNUu Iu

USIM

ME

Cu

UE

Node B

Node B

Node B

Node B

RNC

RNC

Iub Iur

UTRAN

MSCVLR GMSC

SGSN GGSN

HLR

Core Network

PLMN PSTNISDN hellip etc

Internet

ExternalNetworks

bullPLMN Public Land Mobile Network One PLMN is operated by a single operator

8

User Equipment (UE)The UE consists of two parts

The Mobile Equipment (ME) is the radio terminal used for radio communication over the Uu interfaceThe UMTS Subscriber Identity Module (USIM) is a smartcard that holds the subscriber identity performs authentication algorithms and stores authentication and encryption keys and some subscription information that is needed at the terminal

UTRAN consists of two distinct elementsThe Node B converts the data flow between the Iub and Uuinterfaces It also participates in radio resource managementThe Radio Network Controller (RNC) owns and controls the radio resources in its domain (the Node Bs connected to it) RNC is the service access point for all services UTRAN provides the core network (CN)

9

WCDMA System Architecture

UMTS system utilizes the same well-known architecture that has been used by all main 2nd generation systemsThe network elements are grouped into

The Radio Access Network (RAN UMTS Terrestrial RAN = UTRAN) that handles all radio-related functionalityThe Core Network (CN) which is responsible for switching and routing calls and data connections to external networks

Both User Equipment (UE) and UTRAN consist of completely new protocols which is based on the new WCDMA radio technologyThe definition of CN is adopted from GSM

10

Main Elements of the GSM Core Network

HLR (Home Location Register) is a database located in the userrsquos home system that stores the master copy of the userrsquos service profile

The service profile consists of for example information on allowed services forbidden roaming areas and Supplementary Service information such as status of call forwarding and the call forwarding numberIt is created when a new user subscribes to the systemHLR stores the UE location on the level of MSCVLR andor SGSN

11

MSCVLR (Mobile Services Switching Center Visitor Location Register) is the switch (MSC) and database (VLR) that serves the UE in its current location for circuit switched services

The MSC function is used to switch the CS transactionsThe VLR function holds a copy of the visiting userrsquos service profile as well as more precise information on the UErsquoslocation within the serving system

Main Elements of the GSM Core Network

12

GMSC (Gateway MSC) is the switch at the point where UMTS PLMN is connected to external CS networks

All incoming and outgoing circuit switched connections go through GMSC

SGSN (Serving GPRS (General Packet Radio Service) Support Node) functionality is similar to that of MSCVLR but is typically used for Packet Switched (PS) servicesGGSN (Gateway GPRS Support Node) functionality is close to that of GMSC but is in relation to PS services

Main Elements of the GSM Core Network

13

InterfacesCu Interface this is the electrical interface between the USIM smartcard and the ME The interface follows a standard format for smartcardsUu Interface this is the WCDMA radio interface which is the subject of the main part of WCDMA technology This is also the most important open interface in UMTSIu Interface this connects UTRAN to the CNIur Interface the open Iur interface allows soft handover between RNCs from different manufacturersIub Interface the Iub connects a Node B and an RNC UMTS is the first commercial mobile telephony system where the Controller-Base Station interface is standardized as a fully open interface

14

WCDMA Physical Layer General Description (3GPP TS 25201)

15

Elements of A Digital Communications System

Information Bits

)(ˆ tsi

Format SourceEncoding Encryption Channel

Encoding Multiplexing Modulation FrequencySpreading

MultipleAccess

TXRFPA

BitStream

DigitalWaveformSynchronization

CHANNEL

Source Bits Channel Bits

Channel BitsSource Bits

)(tsiDigitalInput

im

DigitalOutput

im

Information Sink

From Other Sources

To Other Destinations

Optional

Essential

Interleaving

Format SourceDecoding Decryption Channel

Decoding Demultiplexing Demodulation FrequencyDespreading

MultipleAccess

RXRFIF

Deinterleaving

16

Establishes the characteristics of the layer-1 transport channels and physical channels in the FDD mode and specifies

Transport channelsPhysical channels and their structureRelative timing between different physical

channels in the same link and relative timing between uplink and downlink

Mapping of transport channels onto the physical channels

Physical channels and mapping of transport channels onto physical channels (FDD)

TS 25211

Describes the contents of the layer 1 documents (TS 25200 series) where to find information a general description of layer 1

Physical Layer ndashgeneral description

TS 25201

3GPP (Radio Access Network) RAN Specifications

17

Establishes the characteristics of the spreading and modulation in the FDD mode and specifies

SpreadingGeneration of channelization and scrambling codesGeneration of random access preamble codesGeneration of synchronization codesModulation

Spreading and Modulation (FDD)

TS 25213

Describes multiplexing channel coding and interleaving in the FDD mode and specifies

Coding and multiplexing of transport channelsChannel coding alternativesCoding for layer 1 control informationDifferent interleaversRate matchingPhysical channel segmentation and mapping

Multiplexing and Channel Coding (FDD)

TS 25212

3GPP (Radio Access Network) RAN Specifications

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 8: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

8

User Equipment (UE)The UE consists of two parts

The Mobile Equipment (ME) is the radio terminal used for radio communication over the Uu interfaceThe UMTS Subscriber Identity Module (USIM) is a smartcard that holds the subscriber identity performs authentication algorithms and stores authentication and encryption keys and some subscription information that is needed at the terminal

UTRAN consists of two distinct elementsThe Node B converts the data flow between the Iub and Uuinterfaces It also participates in radio resource managementThe Radio Network Controller (RNC) owns and controls the radio resources in its domain (the Node Bs connected to it) RNC is the service access point for all services UTRAN provides the core network (CN)

9

WCDMA System Architecture

UMTS system utilizes the same well-known architecture that has been used by all main 2nd generation systemsThe network elements are grouped into

The Radio Access Network (RAN UMTS Terrestrial RAN = UTRAN) that handles all radio-related functionalityThe Core Network (CN) which is responsible for switching and routing calls and data connections to external networks

Both User Equipment (UE) and UTRAN consist of completely new protocols which is based on the new WCDMA radio technologyThe definition of CN is adopted from GSM

10

Main Elements of the GSM Core Network

HLR (Home Location Register) is a database located in the userrsquos home system that stores the master copy of the userrsquos service profile

The service profile consists of for example information on allowed services forbidden roaming areas and Supplementary Service information such as status of call forwarding and the call forwarding numberIt is created when a new user subscribes to the systemHLR stores the UE location on the level of MSCVLR andor SGSN

11

MSCVLR (Mobile Services Switching Center Visitor Location Register) is the switch (MSC) and database (VLR) that serves the UE in its current location for circuit switched services

The MSC function is used to switch the CS transactionsThe VLR function holds a copy of the visiting userrsquos service profile as well as more precise information on the UErsquoslocation within the serving system

Main Elements of the GSM Core Network

12

GMSC (Gateway MSC) is the switch at the point where UMTS PLMN is connected to external CS networks

All incoming and outgoing circuit switched connections go through GMSC

SGSN (Serving GPRS (General Packet Radio Service) Support Node) functionality is similar to that of MSCVLR but is typically used for Packet Switched (PS) servicesGGSN (Gateway GPRS Support Node) functionality is close to that of GMSC but is in relation to PS services

Main Elements of the GSM Core Network

13

InterfacesCu Interface this is the electrical interface between the USIM smartcard and the ME The interface follows a standard format for smartcardsUu Interface this is the WCDMA radio interface which is the subject of the main part of WCDMA technology This is also the most important open interface in UMTSIu Interface this connects UTRAN to the CNIur Interface the open Iur interface allows soft handover between RNCs from different manufacturersIub Interface the Iub connects a Node B and an RNC UMTS is the first commercial mobile telephony system where the Controller-Base Station interface is standardized as a fully open interface

14

WCDMA Physical Layer General Description (3GPP TS 25201)

15

Elements of A Digital Communications System

Information Bits

)(ˆ tsi

Format SourceEncoding Encryption Channel

Encoding Multiplexing Modulation FrequencySpreading

MultipleAccess

TXRFPA

BitStream

DigitalWaveformSynchronization

CHANNEL

Source Bits Channel Bits

Channel BitsSource Bits

)(tsiDigitalInput

im

DigitalOutput

im

Information Sink

From Other Sources

To Other Destinations

Optional

Essential

Interleaving

Format SourceDecoding Decryption Channel

Decoding Demultiplexing Demodulation FrequencyDespreading

MultipleAccess

RXRFIF

Deinterleaving

16

Establishes the characteristics of the layer-1 transport channels and physical channels in the FDD mode and specifies

Transport channelsPhysical channels and their structureRelative timing between different physical

channels in the same link and relative timing between uplink and downlink

Mapping of transport channels onto the physical channels

Physical channels and mapping of transport channels onto physical channels (FDD)

TS 25211

Describes the contents of the layer 1 documents (TS 25200 series) where to find information a general description of layer 1

Physical Layer ndashgeneral description

TS 25201

3GPP (Radio Access Network) RAN Specifications

17

Establishes the characteristics of the spreading and modulation in the FDD mode and specifies

SpreadingGeneration of channelization and scrambling codesGeneration of random access preamble codesGeneration of synchronization codesModulation

Spreading and Modulation (FDD)

TS 25213

Describes multiplexing channel coding and interleaving in the FDD mode and specifies

Coding and multiplexing of transport channelsChannel coding alternativesCoding for layer 1 control informationDifferent interleaversRate matchingPhysical channel segmentation and mapping

Multiplexing and Channel Coding (FDD)

TS 25212

3GPP (Radio Access Network) RAN Specifications

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 9: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

9

WCDMA System Architecture

UMTS system utilizes the same well-known architecture that has been used by all main 2nd generation systemsThe network elements are grouped into

The Radio Access Network (RAN UMTS Terrestrial RAN = UTRAN) that handles all radio-related functionalityThe Core Network (CN) which is responsible for switching and routing calls and data connections to external networks

Both User Equipment (UE) and UTRAN consist of completely new protocols which is based on the new WCDMA radio technologyThe definition of CN is adopted from GSM

10

Main Elements of the GSM Core Network

HLR (Home Location Register) is a database located in the userrsquos home system that stores the master copy of the userrsquos service profile

The service profile consists of for example information on allowed services forbidden roaming areas and Supplementary Service information such as status of call forwarding and the call forwarding numberIt is created when a new user subscribes to the systemHLR stores the UE location on the level of MSCVLR andor SGSN

11

MSCVLR (Mobile Services Switching Center Visitor Location Register) is the switch (MSC) and database (VLR) that serves the UE in its current location for circuit switched services

The MSC function is used to switch the CS transactionsThe VLR function holds a copy of the visiting userrsquos service profile as well as more precise information on the UErsquoslocation within the serving system

Main Elements of the GSM Core Network

12

GMSC (Gateway MSC) is the switch at the point where UMTS PLMN is connected to external CS networks

All incoming and outgoing circuit switched connections go through GMSC

SGSN (Serving GPRS (General Packet Radio Service) Support Node) functionality is similar to that of MSCVLR but is typically used for Packet Switched (PS) servicesGGSN (Gateway GPRS Support Node) functionality is close to that of GMSC but is in relation to PS services

Main Elements of the GSM Core Network

13

InterfacesCu Interface this is the electrical interface between the USIM smartcard and the ME The interface follows a standard format for smartcardsUu Interface this is the WCDMA radio interface which is the subject of the main part of WCDMA technology This is also the most important open interface in UMTSIu Interface this connects UTRAN to the CNIur Interface the open Iur interface allows soft handover between RNCs from different manufacturersIub Interface the Iub connects a Node B and an RNC UMTS is the first commercial mobile telephony system where the Controller-Base Station interface is standardized as a fully open interface

14

WCDMA Physical Layer General Description (3GPP TS 25201)

15

Elements of A Digital Communications System

Information Bits

)(ˆ tsi

Format SourceEncoding Encryption Channel

Encoding Multiplexing Modulation FrequencySpreading

MultipleAccess

TXRFPA

BitStream

DigitalWaveformSynchronization

CHANNEL

Source Bits Channel Bits

Channel BitsSource Bits

)(tsiDigitalInput

im

DigitalOutput

im

Information Sink

From Other Sources

To Other Destinations

Optional

Essential

Interleaving

Format SourceDecoding Decryption Channel

Decoding Demultiplexing Demodulation FrequencyDespreading

MultipleAccess

RXRFIF

Deinterleaving

16

Establishes the characteristics of the layer-1 transport channels and physical channels in the FDD mode and specifies

Transport channelsPhysical channels and their structureRelative timing between different physical

channels in the same link and relative timing between uplink and downlink

Mapping of transport channels onto the physical channels

Physical channels and mapping of transport channels onto physical channels (FDD)

TS 25211

Describes the contents of the layer 1 documents (TS 25200 series) where to find information a general description of layer 1

Physical Layer ndashgeneral description

TS 25201

3GPP (Radio Access Network) RAN Specifications

17

Establishes the characteristics of the spreading and modulation in the FDD mode and specifies

SpreadingGeneration of channelization and scrambling codesGeneration of random access preamble codesGeneration of synchronization codesModulation

Spreading and Modulation (FDD)

TS 25213

Describes multiplexing channel coding and interleaving in the FDD mode and specifies

Coding and multiplexing of transport channelsChannel coding alternativesCoding for layer 1 control informationDifferent interleaversRate matchingPhysical channel segmentation and mapping

Multiplexing and Channel Coding (FDD)

TS 25212

3GPP (Radio Access Network) RAN Specifications

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 10: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

10

Main Elements of the GSM Core Network

HLR (Home Location Register) is a database located in the userrsquos home system that stores the master copy of the userrsquos service profile

The service profile consists of for example information on allowed services forbidden roaming areas and Supplementary Service information such as status of call forwarding and the call forwarding numberIt is created when a new user subscribes to the systemHLR stores the UE location on the level of MSCVLR andor SGSN

11

MSCVLR (Mobile Services Switching Center Visitor Location Register) is the switch (MSC) and database (VLR) that serves the UE in its current location for circuit switched services

The MSC function is used to switch the CS transactionsThe VLR function holds a copy of the visiting userrsquos service profile as well as more precise information on the UErsquoslocation within the serving system

Main Elements of the GSM Core Network

12

GMSC (Gateway MSC) is the switch at the point where UMTS PLMN is connected to external CS networks

All incoming and outgoing circuit switched connections go through GMSC

SGSN (Serving GPRS (General Packet Radio Service) Support Node) functionality is similar to that of MSCVLR but is typically used for Packet Switched (PS) servicesGGSN (Gateway GPRS Support Node) functionality is close to that of GMSC but is in relation to PS services

Main Elements of the GSM Core Network

13

InterfacesCu Interface this is the electrical interface between the USIM smartcard and the ME The interface follows a standard format for smartcardsUu Interface this is the WCDMA radio interface which is the subject of the main part of WCDMA technology This is also the most important open interface in UMTSIu Interface this connects UTRAN to the CNIur Interface the open Iur interface allows soft handover between RNCs from different manufacturersIub Interface the Iub connects a Node B and an RNC UMTS is the first commercial mobile telephony system where the Controller-Base Station interface is standardized as a fully open interface

14

WCDMA Physical Layer General Description (3GPP TS 25201)

15

Elements of A Digital Communications System

Information Bits

)(ˆ tsi

Format SourceEncoding Encryption Channel

Encoding Multiplexing Modulation FrequencySpreading

MultipleAccess

TXRFPA

BitStream

DigitalWaveformSynchronization

CHANNEL

Source Bits Channel Bits

Channel BitsSource Bits

)(tsiDigitalInput

im

DigitalOutput

im

Information Sink

From Other Sources

To Other Destinations

Optional

Essential

Interleaving

Format SourceDecoding Decryption Channel

Decoding Demultiplexing Demodulation FrequencyDespreading

MultipleAccess

RXRFIF

Deinterleaving

16

Establishes the characteristics of the layer-1 transport channels and physical channels in the FDD mode and specifies

Transport channelsPhysical channels and their structureRelative timing between different physical

channels in the same link and relative timing between uplink and downlink

Mapping of transport channels onto the physical channels

Physical channels and mapping of transport channels onto physical channels (FDD)

TS 25211

Describes the contents of the layer 1 documents (TS 25200 series) where to find information a general description of layer 1

Physical Layer ndashgeneral description

TS 25201

3GPP (Radio Access Network) RAN Specifications

17

Establishes the characteristics of the spreading and modulation in the FDD mode and specifies

SpreadingGeneration of channelization and scrambling codesGeneration of random access preamble codesGeneration of synchronization codesModulation

Spreading and Modulation (FDD)

TS 25213

Describes multiplexing channel coding and interleaving in the FDD mode and specifies

Coding and multiplexing of transport channelsChannel coding alternativesCoding for layer 1 control informationDifferent interleaversRate matchingPhysical channel segmentation and mapping

Multiplexing and Channel Coding (FDD)

TS 25212

3GPP (Radio Access Network) RAN Specifications

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 11: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

11

MSCVLR (Mobile Services Switching Center Visitor Location Register) is the switch (MSC) and database (VLR) that serves the UE in its current location for circuit switched services

The MSC function is used to switch the CS transactionsThe VLR function holds a copy of the visiting userrsquos service profile as well as more precise information on the UErsquoslocation within the serving system

Main Elements of the GSM Core Network

12

GMSC (Gateway MSC) is the switch at the point where UMTS PLMN is connected to external CS networks

All incoming and outgoing circuit switched connections go through GMSC

SGSN (Serving GPRS (General Packet Radio Service) Support Node) functionality is similar to that of MSCVLR but is typically used for Packet Switched (PS) servicesGGSN (Gateway GPRS Support Node) functionality is close to that of GMSC but is in relation to PS services

Main Elements of the GSM Core Network

13

InterfacesCu Interface this is the electrical interface between the USIM smartcard and the ME The interface follows a standard format for smartcardsUu Interface this is the WCDMA radio interface which is the subject of the main part of WCDMA technology This is also the most important open interface in UMTSIu Interface this connects UTRAN to the CNIur Interface the open Iur interface allows soft handover between RNCs from different manufacturersIub Interface the Iub connects a Node B and an RNC UMTS is the first commercial mobile telephony system where the Controller-Base Station interface is standardized as a fully open interface

14

WCDMA Physical Layer General Description (3GPP TS 25201)

15

Elements of A Digital Communications System

Information Bits

)(ˆ tsi

Format SourceEncoding Encryption Channel

Encoding Multiplexing Modulation FrequencySpreading

MultipleAccess

TXRFPA

BitStream

DigitalWaveformSynchronization

CHANNEL

Source Bits Channel Bits

Channel BitsSource Bits

)(tsiDigitalInput

im

DigitalOutput

im

Information Sink

From Other Sources

To Other Destinations

Optional

Essential

Interleaving

Format SourceDecoding Decryption Channel

Decoding Demultiplexing Demodulation FrequencyDespreading

MultipleAccess

RXRFIF

Deinterleaving

16

Establishes the characteristics of the layer-1 transport channels and physical channels in the FDD mode and specifies

Transport channelsPhysical channels and their structureRelative timing between different physical

channels in the same link and relative timing between uplink and downlink

Mapping of transport channels onto the physical channels

Physical channels and mapping of transport channels onto physical channels (FDD)

TS 25211

Describes the contents of the layer 1 documents (TS 25200 series) where to find information a general description of layer 1

Physical Layer ndashgeneral description

TS 25201

3GPP (Radio Access Network) RAN Specifications

17

Establishes the characteristics of the spreading and modulation in the FDD mode and specifies

SpreadingGeneration of channelization and scrambling codesGeneration of random access preamble codesGeneration of synchronization codesModulation

Spreading and Modulation (FDD)

TS 25213

Describes multiplexing channel coding and interleaving in the FDD mode and specifies

Coding and multiplexing of transport channelsChannel coding alternativesCoding for layer 1 control informationDifferent interleaversRate matchingPhysical channel segmentation and mapping

Multiplexing and Channel Coding (FDD)

TS 25212

3GPP (Radio Access Network) RAN Specifications

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 12: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

12

GMSC (Gateway MSC) is the switch at the point where UMTS PLMN is connected to external CS networks

All incoming and outgoing circuit switched connections go through GMSC

SGSN (Serving GPRS (General Packet Radio Service) Support Node) functionality is similar to that of MSCVLR but is typically used for Packet Switched (PS) servicesGGSN (Gateway GPRS Support Node) functionality is close to that of GMSC but is in relation to PS services

Main Elements of the GSM Core Network

13

InterfacesCu Interface this is the electrical interface between the USIM smartcard and the ME The interface follows a standard format for smartcardsUu Interface this is the WCDMA radio interface which is the subject of the main part of WCDMA technology This is also the most important open interface in UMTSIu Interface this connects UTRAN to the CNIur Interface the open Iur interface allows soft handover between RNCs from different manufacturersIub Interface the Iub connects a Node B and an RNC UMTS is the first commercial mobile telephony system where the Controller-Base Station interface is standardized as a fully open interface

14

WCDMA Physical Layer General Description (3GPP TS 25201)

15

Elements of A Digital Communications System

Information Bits

)(ˆ tsi

Format SourceEncoding Encryption Channel

Encoding Multiplexing Modulation FrequencySpreading

MultipleAccess

TXRFPA

BitStream

DigitalWaveformSynchronization

CHANNEL

Source Bits Channel Bits

Channel BitsSource Bits

)(tsiDigitalInput

im

DigitalOutput

im

Information Sink

From Other Sources

To Other Destinations

Optional

Essential

Interleaving

Format SourceDecoding Decryption Channel

Decoding Demultiplexing Demodulation FrequencyDespreading

MultipleAccess

RXRFIF

Deinterleaving

16

Establishes the characteristics of the layer-1 transport channels and physical channels in the FDD mode and specifies

Transport channelsPhysical channels and their structureRelative timing between different physical

channels in the same link and relative timing between uplink and downlink

Mapping of transport channels onto the physical channels

Physical channels and mapping of transport channels onto physical channels (FDD)

TS 25211

Describes the contents of the layer 1 documents (TS 25200 series) where to find information a general description of layer 1

Physical Layer ndashgeneral description

TS 25201

3GPP (Radio Access Network) RAN Specifications

17

Establishes the characteristics of the spreading and modulation in the FDD mode and specifies

SpreadingGeneration of channelization and scrambling codesGeneration of random access preamble codesGeneration of synchronization codesModulation

Spreading and Modulation (FDD)

TS 25213

Describes multiplexing channel coding and interleaving in the FDD mode and specifies

Coding and multiplexing of transport channelsChannel coding alternativesCoding for layer 1 control informationDifferent interleaversRate matchingPhysical channel segmentation and mapping

Multiplexing and Channel Coding (FDD)

TS 25212

3GPP (Radio Access Network) RAN Specifications

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 13: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

13

InterfacesCu Interface this is the electrical interface between the USIM smartcard and the ME The interface follows a standard format for smartcardsUu Interface this is the WCDMA radio interface which is the subject of the main part of WCDMA technology This is also the most important open interface in UMTSIu Interface this connects UTRAN to the CNIur Interface the open Iur interface allows soft handover between RNCs from different manufacturersIub Interface the Iub connects a Node B and an RNC UMTS is the first commercial mobile telephony system where the Controller-Base Station interface is standardized as a fully open interface

14

WCDMA Physical Layer General Description (3GPP TS 25201)

15

Elements of A Digital Communications System

Information Bits

)(ˆ tsi

Format SourceEncoding Encryption Channel

Encoding Multiplexing Modulation FrequencySpreading

MultipleAccess

TXRFPA

BitStream

DigitalWaveformSynchronization

CHANNEL

Source Bits Channel Bits

Channel BitsSource Bits

)(tsiDigitalInput

im

DigitalOutput

im

Information Sink

From Other Sources

To Other Destinations

Optional

Essential

Interleaving

Format SourceDecoding Decryption Channel

Decoding Demultiplexing Demodulation FrequencyDespreading

MultipleAccess

RXRFIF

Deinterleaving

16

Establishes the characteristics of the layer-1 transport channels and physical channels in the FDD mode and specifies

Transport channelsPhysical channels and their structureRelative timing between different physical

channels in the same link and relative timing between uplink and downlink

Mapping of transport channels onto the physical channels

Physical channels and mapping of transport channels onto physical channels (FDD)

TS 25211

Describes the contents of the layer 1 documents (TS 25200 series) where to find information a general description of layer 1

Physical Layer ndashgeneral description

TS 25201

3GPP (Radio Access Network) RAN Specifications

17

Establishes the characteristics of the spreading and modulation in the FDD mode and specifies

SpreadingGeneration of channelization and scrambling codesGeneration of random access preamble codesGeneration of synchronization codesModulation

Spreading and Modulation (FDD)

TS 25213

Describes multiplexing channel coding and interleaving in the FDD mode and specifies

Coding and multiplexing of transport channelsChannel coding alternativesCoding for layer 1 control informationDifferent interleaversRate matchingPhysical channel segmentation and mapping

Multiplexing and Channel Coding (FDD)

TS 25212

3GPP (Radio Access Network) RAN Specifications

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 14: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

14

WCDMA Physical Layer General Description (3GPP TS 25201)

15

Elements of A Digital Communications System

Information Bits

)(ˆ tsi

Format SourceEncoding Encryption Channel

Encoding Multiplexing Modulation FrequencySpreading

MultipleAccess

TXRFPA

BitStream

DigitalWaveformSynchronization

CHANNEL

Source Bits Channel Bits

Channel BitsSource Bits

)(tsiDigitalInput

im

DigitalOutput

im

Information Sink

From Other Sources

To Other Destinations

Optional

Essential

Interleaving

Format SourceDecoding Decryption Channel

Decoding Demultiplexing Demodulation FrequencyDespreading

MultipleAccess

RXRFIF

Deinterleaving

16

Establishes the characteristics of the layer-1 transport channels and physical channels in the FDD mode and specifies

Transport channelsPhysical channels and their structureRelative timing between different physical

channels in the same link and relative timing between uplink and downlink

Mapping of transport channels onto the physical channels

Physical channels and mapping of transport channels onto physical channels (FDD)

TS 25211

Describes the contents of the layer 1 documents (TS 25200 series) where to find information a general description of layer 1

Physical Layer ndashgeneral description

TS 25201

3GPP (Radio Access Network) RAN Specifications

17

Establishes the characteristics of the spreading and modulation in the FDD mode and specifies

SpreadingGeneration of channelization and scrambling codesGeneration of random access preamble codesGeneration of synchronization codesModulation

Spreading and Modulation (FDD)

TS 25213

Describes multiplexing channel coding and interleaving in the FDD mode and specifies

Coding and multiplexing of transport channelsChannel coding alternativesCoding for layer 1 control informationDifferent interleaversRate matchingPhysical channel segmentation and mapping

Multiplexing and Channel Coding (FDD)

TS 25212

3GPP (Radio Access Network) RAN Specifications

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 15: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

15

Elements of A Digital Communications System

Information Bits

)(ˆ tsi

Format SourceEncoding Encryption Channel

Encoding Multiplexing Modulation FrequencySpreading

MultipleAccess

TXRFPA

BitStream

DigitalWaveformSynchronization

CHANNEL

Source Bits Channel Bits

Channel BitsSource Bits

)(tsiDigitalInput

im

DigitalOutput

im

Information Sink

From Other Sources

To Other Destinations

Optional

Essential

Interleaving

Format SourceDecoding Decryption Channel

Decoding Demultiplexing Demodulation FrequencyDespreading

MultipleAccess

RXRFIF

Deinterleaving

16

Establishes the characteristics of the layer-1 transport channels and physical channels in the FDD mode and specifies

Transport channelsPhysical channels and their structureRelative timing between different physical

channels in the same link and relative timing between uplink and downlink

Mapping of transport channels onto the physical channels

Physical channels and mapping of transport channels onto physical channels (FDD)

TS 25211

Describes the contents of the layer 1 documents (TS 25200 series) where to find information a general description of layer 1

Physical Layer ndashgeneral description

TS 25201

3GPP (Radio Access Network) RAN Specifications

17

Establishes the characteristics of the spreading and modulation in the FDD mode and specifies

SpreadingGeneration of channelization and scrambling codesGeneration of random access preamble codesGeneration of synchronization codesModulation

Spreading and Modulation (FDD)

TS 25213

Describes multiplexing channel coding and interleaving in the FDD mode and specifies

Coding and multiplexing of transport channelsChannel coding alternativesCoding for layer 1 control informationDifferent interleaversRate matchingPhysical channel segmentation and mapping

Multiplexing and Channel Coding (FDD)

TS 25212

3GPP (Radio Access Network) RAN Specifications

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 16: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

16

Establishes the characteristics of the layer-1 transport channels and physical channels in the FDD mode and specifies

Transport channelsPhysical channels and their structureRelative timing between different physical

channels in the same link and relative timing between uplink and downlink

Mapping of transport channels onto the physical channels

Physical channels and mapping of transport channels onto physical channels (FDD)

TS 25211

Describes the contents of the layer 1 documents (TS 25200 series) where to find information a general description of layer 1

Physical Layer ndashgeneral description

TS 25201

3GPP (Radio Access Network) RAN Specifications

17

Establishes the characteristics of the spreading and modulation in the FDD mode and specifies

SpreadingGeneration of channelization and scrambling codesGeneration of random access preamble codesGeneration of synchronization codesModulation

Spreading and Modulation (FDD)

TS 25213

Describes multiplexing channel coding and interleaving in the FDD mode and specifies

Coding and multiplexing of transport channelsChannel coding alternativesCoding for layer 1 control informationDifferent interleaversRate matchingPhysical channel segmentation and mapping

Multiplexing and Channel Coding (FDD)

TS 25212

3GPP (Radio Access Network) RAN Specifications

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 17: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

17

Establishes the characteristics of the spreading and modulation in the FDD mode and specifies

SpreadingGeneration of channelization and scrambling codesGeneration of random access preamble codesGeneration of synchronization codesModulation

Spreading and Modulation (FDD)

TS 25213

Describes multiplexing channel coding and interleaving in the FDD mode and specifies

Coding and multiplexing of transport channelsChannel coding alternativesCoding for layer 1 control informationDifferent interleaversRate matchingPhysical channel segmentation and mapping

Multiplexing and Channel Coding (FDD)

TS 25212

3GPP (Radio Access Network) RAN Specifications

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 18: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

18

Establishes the characteristics of the physical layer measurements in the FDD mode and specifies

The measurements performance by layer 1Reporting of measurements to higher layers and

networkHandover measurements and idle-mode

measurements

Physical Layer Measurements (FDD)

TS 25215

Establishes the characteristics of the physical layer procedures in the FDD mode and specifies

Cell search proceduresPower control proceduresRandom access procedure

Physical Layer Procedures (FDD)

TS 25214

3GPP (Radio Access Network) RAN Specifications

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 19: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

19

General Protocol ArchitectureRadio interface means the Uu point between User Equipment (UE) and networkThe radio interface is composed of Layers 1 2 and 3

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layer

Con

trol

Mea

sure

men

ts

Layer 3

Logical channelsLayer 2

Layer 1

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 20: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

20

General Protocol ArchitectureThe circles between different layersub-layers indicate service access points (SAPs)The physical layer offers different transport channels to MAC

A transport channel is characterized by how the information is transferred over the radio interface

MAC offers different logical channels to the radio link control (RLC) sub-layer of Layer 2

A logical channel is characterized by the type of information transferred

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 21: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

21

Transport Channels

Transport channels are services offered by Layer 1 to the higher layersA transport channel is defined by how and with what characteristics data is transferred over the air interface

Two groups of transport channelsDedicated Transport Channels

Common Transport Channels

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 22: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

22

Transport channelsDedicated Transport Channels

DCH ndash Dedicated Channel (only one type)

Common Transport Channels ndash divided between all or a group of users in a cell (no soft handover but some of them can have fast power control)

BCH Broadcast Channel

FACH Forward Access Channel

PCH Paging Channel

RACH Random Access Channel

CPCH Common Packet Channel

DSCH DL Shared Channel

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 23: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

23

Dedicated Transport Channels

There exists only one type of dedicated transport channel the Dedicated Channel (DCH)The Dedicated Channel (DCH) is a downlink or uplink transport channelThe DCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDCH carries both the service data such as speech frames and higher layer control information such as handover commands or measurement reports from the terminalPossibility of fast rate change (every 10 ms)Support of fast power control and soft handover

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 24: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

24

Common Transport ChannelBroadcast Channel (BCH) -- mandatory

BCH is a downlink transport channel that is used to broadcast system and cell specific informationBCH is always transmitted over the entire cellThe most typical data needed in every network is the available random access codes and access slots in the cell or the types of transmit diversityBCH is transmitted with relatively high powerSingle transport format ndash a low and fixed data rate for the UTRA broadcast channel to support low-end terminals

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 25: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

25

Common Transport ChannelPaging Channel (PCH) -- mandatory

PCH is a downlink transport channelPCH is always transmitted over the entire cellPCH carries data relevant to the paging procedure that is when the network wants to initiate communication with the terminalThe identical paging message can be transmitted in a single cell or in up to a few hundreds of cells depending on the system configuration

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 26: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

26

Common Transport ChannelRandom Access Channel (RACH) -- mandatory

RACH is an uplink transport channelRACH is intended to be used to carry control information from the terminal such as requests to set up a connectionRACH can also be used to send small amounts of packet data from the terminal to the networkThe RACH is always received from the entire cellThe RACH is characterized by a collision riskRACH is transmitted using open loop power control

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 27: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

27

Common Transport ChannelForward Access Channel (FACH) -- mandatory

FACH is a downlink transport channelFACH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasFACH can carry control information for example after a random access message has been received by the base stationFACH can also transmit packet dataFACH does not use fast power controlFACH can be transmitted using slow power controlThere can be more than one FACH in a cellThe messages transmitted need to include in-band identification information

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 28: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

28

Common Transport ChannelCommon Packet Channel (CPCH) -- optional

CPCH is an uplink transport channelCPCH is an extension to the RACH channel that is intended to carry packet-based user dataCPCH is associated with a dedicated channel on the downlink which provides power control and CPCH Control Commands (eg Emergency Stop) for the uplink CPCHThe CPCH is characterised by initial collision risk and by being transmitted using inner loop power controlCPCH may last several frames

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 29: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

29

Common Transport ChannelDownlink Shared Channel (DSCH) -- optional

DSCH is a downlink transport channel shared by several UEsto carry dedicated user data andor control informationThe DSCH is always associated with one or several downlink DCHThe DSCH is transmitted over the entire cell or over only a part of the cell using eg beam-forming antennasDSCH supports fast power control as well as variable bit rate on a frame-by-frame basis

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 30: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

30

Mapping of Transport Channels onto Physical Channels

Transport Channels

DCH

RACH

CPCH

BCH

FACH

PCH

Physical Channels

Dedicated Physical Data Channel (DPDCH)

Dedicated Physical Control Channel (DPCCH)

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

DSCH Physical Downlink Shared Channel (PDSCH)

Common Pilot Channel (CPICH)Synchronization Channel (SCH)

Acquisition Indicator Channel (AICH)

Access Preamble Acquisition Indicator Channel (AP-AICH)

Paging Indicator Channel (PICH)

CPCH Status Indicator Channel (CSICH)

Collision-DetectionChannel-Assignment Indicator Channel

(CDCA-ICH)⎪⎪⎪⎪

⎪⎪⎪⎪

Unmapped

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 31: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

31

Multiplexing and Channel Coding( 3GPP TS 25212 )

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 32: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

32

UL Multiplexing and Channel Coding

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 33: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

33

DL Multiplexing and Channel Coding

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 34: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

34

CRC-AttachmentCRC-attachment

For error detectiongCRC24(D) = D24 + D23 + D6 + D5 + D + 1gCRC16(D) = D16 + D12 + D5 + 1gCRC12(D) = D12 + D11 + D3 + D2 + D + 1gCRC8(D) = D8 + D7 + D4 + D3 + D + 1

TrBk

TrBk

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 35: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

35

Channel CodingUsage of coding scheme and coding rate

No coding13Turbo coding

13 12CPCH DCH DSCH FACH

RACHPCH

12Convolutional codingBCH

Coding rateCoding schemeType of TrCH

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 36: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

36

WCDMA Uplink Physical Layer( 3GPP TS 25211 amp 25213 )

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 37: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

37

OverviewConfiguration

Radio frameA radio frame is a processing unit which consists of 15 slotsThe length of a radio frame corresponds to 38400 chips

Time slotA time slot is a unit which consists of fields containing bitsThe length of a slot corresponds to 2560 chips

Spreading Modulation QPSKData Modulation BPSKSpreading

Two-level spreading processes

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 38: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

38

OverviewSpreading (cont)

Channelization operationOVSF codesTransform every data symbol into a number of chipsIncrease the bandwidth of the signalThe number of chips per data symbol is called the Spreading FactorData symbols on I- and Q-branches are independently multiplied with an OVSF code

Scrambling operationLong or short Gold codesApplied to the spread signalsRandomize the codes

Spread signal is further multiplied by complex-valued scrambling

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 39: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

39

Uplink Physical Channels

Dedicated Uplink Physical ChannelsUplink Dedicated Physical Data Channel (UL DPDCH)Uplink Dedicated Physical Control Channel (UL DPCCH)

Common Uplink Physical ChannelsPhysical Random Access Channel (PRACH)Physical Common Packet Channel (PCPCH)

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 40: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

40

Dedicated Uplink Physical ChannelsUL Dedicated Physical Data Channel (UL DPDCH)

Carry the DCH transport channel (generated at Layer 2 and above)There may be zero one or several uplink DPDCHs on each radio link

UL Dedicated Physical Control Channel (UL DPCCH)Carry control information generated at Layer 1One and only one UL DPCCH on each radio link

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 41: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

41

Frame Structure for UL DPDCHDPCCH

PilotNpilot bits

TPCNTPC bits

DataNdata bits

Tslot = 2560 chips 10 bits

1 radio frame Tf = 10 ms = 38400 chips

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits

Tslot = 2560 chips

Slot 0 Slot 1 Slot i Slot 14

Ndata= 102k bits (k=01hellip6)

One Power Control Period

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 42: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

42

UL DPDCHThe parameter k determines the number of bits per uplink DPDCH slotIt is related to the spreading factor SF of the DPDCH as SF = 2562kThe DPDCH spreading factor ranges from 256 down to 4

640640960049609606

320320480084804805

1601602400162402404

80801200321201203

40406006460602

202030012830301

101015025615150

NdataBits Slot

Bits Frame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 43: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

43

UL DPCCH - Layer 1 Control InformationThe spreading factor of the uplink DPCCH is always equal to 256 ie there are 10 bits per uplink DPCCH slot

8-924131015025615155B

10-1423141015025615155A

1522151015025615155

8-1520261015025615154

8-1510271015025615153

8-914231015025615152B

10-1413241015025615152A

1512251015025615152

8-1500281015025615151

8-904241015025615150B

10-1403251015025615150A

1502261015025615150

Transmitted slots per

radio frame

NFBINTFCINTPCNpilotBitsSlot

BitsFrame

SFChannel Symbol Rate

(ksps)

Channel Bit Rate (kbps)

Slot Format i

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 44: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

44

UL DPCCH - Layer 1 Control InformationPilot Bits

Support channel estimation for coherent detectionFrame Synchronization Word (FSW) can be sued to confirm frame synchronizaton

Transmit Power Control (TPC) commandInner loop power control commands

Feedback Information (FBI)Support of close loop transmit diversitySite Selection Diversity Transmission (SSDT)

Transport-Format Combination Indicator (TFCI) ndashoptional

TFCI informs the receiver about the instantaneous transport format combination of the transport channels

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 45: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

45

Pilot Bit Patterns with Npilot=3456

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

101001101110000

100011110101100

111111111111111

111111111111111

101001101110000

100011110101100

Slot 01234567891011121314

543210432103210210Bit Npilot = 6Npilot = 5Npilot = 4Npilot = 3

Shadowed column is defined as FSW (Frame Synchronization Word)

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 46: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

46

Pilot Bit Patterns with Npilot=78

Shadowed column is defined as FSW (Frame Synchronization Word)

001010000111011

111111111111111

110001001101011

111111111111111

101001101110000

111111111111111

100011110101100

111111111111111

111111111111111

001010000111011

110001001101011

111111111111111

101001101110000

100011110101100

111111111111111

Slot 0123456789

1011121314

765432106543210Bit Npilot = 8Npilot = 7

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 47: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

47

j

c d 1 β d

S lo n g n o r S s h o r t n

I+ jQ

D P D C H 1

Q

c d 3 β d

D P D C H 3

c d 5 β d

D P D C H 5

c d 2 β d

D P D C H 2

c d 4 β d

D P D C H 4

c d 6 β d

D P D C H 6

c c β c

D P C C H

Σ

Spreading of UL DPCH

One and only one UL DPCCHUp to six parallel DPDCHs

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 48: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

48

Spreading of UL DPCHThe binary DPCCH and DPDCHs to be spread are represented by real-valued sequences ie the binary value 0 is mapped to the real value +1 while the binary value 1 is mapped to the real value ndash1The DPCCH is spread to the chip rate by the channelization code cc while the nth DPDCH called DPDCHn is spread to the chip rate by the channelizationcode cdnOne DPCCH and up to six parallel DPDCHs can be transmitted simultaneously ie 1 le n le 6

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 49: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

49

Channelization Codes

Each CDMA channel is distinguished via a unique spreading codeThese spreading codes should have low cross-correlation valuesIn 3GPP W-CDMA orthogonal variable spreading factor (OVSF) codes are usedPreserve the orthogonality between a userrsquos different physical channelsScrambling is used on top of spreading

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 50: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

50

Code-tree for Generation of Orthogonal Variable Spreading Factor (OVSF) Codes

SF = 1 SF = 2 SF = 4

Cch10 = (1)

Cch20 = (11)

Cch21 = (1-1)

Cch40 =(1111)

Cch41 = (11-1-1)

Cch42 = (1-11-1)

Cch43 = (1-1-11)

The channelization codes are uniquely described as CchSFk where SF isthe spreading factor of the code and k is the code number 0 le k le SF-1

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 51: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

51

Generation of Channelization Codes1Cch10 =

⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

⎡minus

=⎥⎦

⎤⎢⎣

1111

01

01

01

01

12

02

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( ) ⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minus

minus

minus

=

⎥⎥⎥⎥⎥⎥⎥⎥⎥

⎢⎢⎢⎢⎢⎢⎢⎢⎢

minusminus

minusminus

minus++

minus++

+

+

+

+

122122

122122

1212

1212

0202

0202

11212

21212

312

212

112

012

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCC

CC

CC

CCCC

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 52: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

52

OVSF Code Allocation for UL DPCHDPCCH is always spread by cc= Cch2560

When there is only one DPDCHDPDCH1 is spread by cd1= CchSFk (k= SF 4)

When there are more than one DPDCHAll DPDCHs have SF=4

DPDCHn is spread by the the code cdn = Cch4k

k = 1 if n isin 1 2 k = 3 if n isin 3 4 and k = 2 if n isin 5 6

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 53: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

53

Gain of UL DPCHAfter channelization the real-valued spread signals are weighted by gain factors βc for DPCCH and βd for all DPDCHsAt every instant in time at least one of the valuesβc andβd has the amplitude 10 The β-values are quantized into 4 bit wordsAfter the weighting the stream of real-valued chips on the I- and Q-branches are then summed and treated as a complex-valued stream of chipsThis complex-valued signal is then scrambled by the complex-valued scrambling code Sdpchn

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 54: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

54

Signaling values for βc and βd

Quantized amplitude ratios βc and βd

15 10 14 09333 13 08666 12 08000 11 07333 10 06667 9 06000 8 05333 7 04667 6 04000 5 03333 4 02667 3 02000 2 01333 1 00667 0 Switch off

Gain of UL DPCH

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 55: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

55

Configuration of Uplink Scrambling Sequence Generator

clong1n

clong2n

MSB LSB

x

y

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 56: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

56

Uplink Long Scrambling Codes

Two elementary codes clong1n and clong2n

clong1n and clong2n are constructed from position wise modulo 2 sum of 38400 chip segments of two binary m-sequences x and y

x and y are originated from two generator polynomials of degree 25x sequence generator polynomial X25+X3+1y sequence generator polynomial y25+y3+y2+y+1

The sequence clong2n is a 16777232 chip shifted version of the sequence clong1nclong1n and clong2n are Gold codes

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 57: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

57

Uplink Long Scrambling Codes

For code number nn=[n23 hellip n0 ] with n0 being the LSB

Let xn(i) and y(i) denote the i -th chip of the sequence xn and y

Initial conditionsxn(0)=n0 xn(1)=n1 hellip xn(22)=n22 xn(23)=n23 xn(24)=1

y(0)=y(1)= hellip =y(23)= y(24)=1

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 58: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

58

Uplink Long Scrambling Codes

Recursive formulation i=0hellip 225-27xn(i+25) =xn(i+3) + xn(i) modulo 2

y(i+25) = y(i+3)+y(i+2) +y(i+1)+y(i) modulo 2

Gold sequence zn

zn(i ) = xn(i ) + y (i ) modulo 2 i = 0 1 2 hellip 225-2

22101)(10)(1

)( 25 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 59: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

59

Uplink Long Scrambling Codes

clong1n(i ) = Zn(i ) i = 0 1 2 hellip 225-2

clong2n is a 16777232 chip shifted version of the sequence clong1n

clong2n(i ) = Zn((i + 16777232) modulo (225 ndash 1)) i = 0 1 2 hellip 225-2

⎭⎬⎫

⎩⎨⎧

⎥⎦⎥

⎢⎣⎢minus+= )2

2()1(1)()( 21icjiciC nlong

inlongnlong

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 60: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

60

Uplink Short Scrambling Sequence Generator for 255 Chip Sequence

07 4

+ mod n addition

d(i)12356

2

mod 2

07 4b(i)

12356

2

mod 2

+mod 4multiplication

zn(i)

07 4 12356

+mod 4

Mapper

cshort1n(i)

a(i)

+ + +

+ ++

+ ++

3 3

3

2

cshort2n(i)

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 61: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

61

Uplink Short Scrambling CodesTwo elementary codes cshort1n and cshort2n

256 chips

GenerationFrom the family of periodically extended S(2) codesThe nth quaternary S(2) sequence zn(i ) 0 le n le 16777215 is obtained by modulo 4 addition of three sequences

One quaternary sequence a (i )Two binary sequences b (i ) and d (i )

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 62: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

62

Uplink Short Scrambling Codeszn(i ) = a(i ) + 2b(i ) + 2d (i ) modulo 4 (i = 0 254)Given a code number n =[n23n22hellipn0] quaternary sequence a (i ) g0(x)= x8+x5+3x3+x2+2x+1

Initial conditionsa (0) = 2n0 + 1 modulo 4

a (i) = 2ni modulo 4 i = 1 2 hellip 7

Recursive formulationa (i) = 3a (i-3) + a (i-5) + 3a (i-6) + 2a (i-7) + 3a (i-8) modulo 4 i = 8 9 hellip 254

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 63: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

63

Uplink Short Scrambling CodesBinary sequence b(i) g1(x)= x8+x7+x5+x+1

Initial conditionsB (i ) = n8+i modulo 2 i = 0 1 hellip 7

Recursive formulationb (i) = b (i-1) + b (i-3) + b (i-7) + b (i-8) modulo 2 i = 8 9 hellip 254

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 64: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

64

Uplink Short Scrambling CodesBinary sequence d (i ) g2(x)= x8+x7+x5+x4+1

Initial conditionsd (i ) = n16+i modulo 2 i = 0 1 hellip 7

Recursive formulationd (i ) = d (i-1) + d (i-3) + d (i-4) + d (i-8) modulo 2 i = 8 9 hellip 254

zn(i) = a (i) + 2b (i) + 2d (i) modulo 4 (i = 0 254)

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 65: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

65

Uplink Short Scrambling Codeszn(i) is extended to length 256 chips

zn(255) = zn(0)

Mapping

Cshort n is

zn(i) cshort1n(i) cshort2n(i)0 +1 +11 -1 +12 -1 -13 +1 -1

⎭⎬⎫

⎩⎨⎧

⎟⎠⎞

⎜⎝⎛

⎥⎦⎥

⎢⎣⎢minus+=

2256mod2)1(1)256mod()( 21

icjiciC nshorti

nshortnshort

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 66: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

66

Uplink ModulationThe modulation chip rate is 384 McpsThe complex-valued chip sequence generated by the spreading process is QPSK modulated

S

ImS

ReS

cos(ωt)

Complex-valuedchip sequencefrom spreadingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 67: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

67

Uplink Transmitter Functional Block

DI

DQ

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

TSprimeTS+

+

+

+

IC

IC

QC

Gain Controlch1C

2561C

DPDCH

DPCCH

tAcos cω

tAsin cω

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

sum

+

minus

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 68: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

68

WCDMA Downlink Physical Layer( 3GPP TS 25211 amp 25213 )

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 69: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

69

Table of Contents

IntroductionDedicated Downlink Physical Channels

Downlink Dedicated Physical Channel (DL DPCH)

Common Downlink Physical ChannelsCommon Pilot Channel (CPICH)

Timing RelationshipSpreadingModulation

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 70: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

70

Introduction

Downlink DPCHAICH CPICHCCPCH PICH

IdleMS

On-lineMS

Power-onMS

SCH

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 71: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

71

Downlink Transmit DiversityOpen loop transmit diversity STTD and TSTDClosed loop transmit diversity BS

ˇˇ-DL-DPCCH for CPCH

-ˇ-CDCA-ICH

-ˇ-AP-AICH

ndashˇndashCSICH

ndashˇndashAICH

ˇˇndashPDSCH

ndashˇndashPICH

ˇˇndashDPCH

ndashˇndashS-CCPCH

ndashndashˇSCH

ndashˇndashP-CCPCH

ModeSTTDTSTD

Closed loopOpen loop modePhysical channel type

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 72: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

72

Space Time Block Coding Based Transmit Antenna Diversity (STTD)

The STTD encoding is optional in UTRAN STTD support is mandatory at the UESTTD encoding is applied on blocks of 4 consecutive channel bits

b 0 b 1 b 2 b 3

b 0 b 1 b 2 b 3

-b 2 b 3 b 0 -b 1

A ntenna 1

A ntenna 2C hannel b its

ST T D encoded channel b itsfo r antenna 1 and antenna 2

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 73: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

73

Time Switched Transmit Diversity for SCH (TSTD)

TSTD can be applied to TSTDTSTD for the SCH is optional in UTRAN while TSTD support is mandatory in the UEPrim arySCH

SecondarySCH

256 chips

2560 chips

One 10 m s SCH radio fram e

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

Antenna 1

Antenna 2

acsi0

acp

acsi1

acp

acsi14

acp

Slot 0 Slot 1 Slot 14

acsi2

acp

Slot 2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 74: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

74

Closed Loop Mode Transmit Diversity

Spreadscramblew1

w2

DPCHDPCCH

DPDCH

sum

CPICH1

sum

CPICH2

Ant1

Ant2

Weight Generation

w1 w2

Determine FBI messagefrom Uplink DPCCH

3GPP TS 25214 V390 Sect 7

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 75: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

75

The spread complex valued signal is fed to both TX antenna branches and weighted with antenna specific weight factors w1 and w2 where wi = ai + jbi The weight factors (phase adjustments in closed loop mode 1 and phaseamplitude adjustments in closed loop mode 2) are determined by the UE and signalled to the UTRAN access point (=cell transceiver) using the D sub-field of the FBI field of uplink DPCCHFor the closed loop mode 1 different (orthogonal) dedicated pilot symbols in the DPCCH are sent on the 2 different antennas For closed loop mode 2 the same dedicated pilot symbols in the DPCCH are sent on both antennas

Closed Loop Mode Transmit Diversity

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 76: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

76

Number of Feedback Information in Closed Loop Transmit Diversity

Summary of number of feedback information bits per slot NFBD feedback command length in slots NW feedback command rate feedback bit rate number of phase bits Nph per signalling word number of amplitude bits Npo per signalling word and amount of constellation rotation at UE for the two closed loop modes

NA311500 bps1500 Hz412

π2101500 bps1500 Hz111

Constellation rotation

NphNpoFeedback bit rate

Update rateNWNFBDClosed loop mode

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 77: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

77

Determination of Feedback Information in Closed Loop Mode Transmit Diversity

The UE uses the CPICH to separately estimate the channels seen from each antennaOnce every slot the UE computes the phase adjustment φ and for mode 2 the amplitude adjustment that should be applied at the UTRAN access point to maximise the UE received powerThe UE feeds back to the UTRAN access point the information on which phasepower settings to useFeedback Signalling Message (FSM) bits are transmitted in the portion of FBI field of uplink DPCCH slot(s) assigned to closed loop mode transmit diversity the FBI D field Each message is of length NW = Npo+Nph bits

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 78: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

78

Closed Loop Mode 1

The UE uses the CPICH transmitted both from antenna 1 and antenna 2 to calculate the phase adjustment to be applied at UTRAN access point to maximise the UE received powerIn each slot UE calculates the optimum phase adjustment φ for antenna 2 which is then quantized into having two possible values as follows

where

If = 0 a command 0 is sent to UTRAN using the FSMphfield If = π command 1 is sent to UTRAN using the FSMph field

⎩⎨⎧ leminuslt

=otherwise0

23)(2 if πφφππφ

irQ

⎩⎨⎧

==

=1311975312

141210864200)(

ii

ir πφ

QφQφ

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 79: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

79

Closed Loop Mode 2In closed loop mode 2 there are 16 possible combinations of phase and power adjustment

02081

08020

Power_ant2Power_ant1FSMpo

3π4100π2101π41110110

-π4010-π2011-3π4001

π000Phase difference between antennas (radians)FSMph

FSMpo subfield ofsignalling message

FSMph subfield ofsignalling message

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 80: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

80

Downlink Dedicated Physical Channels (DPCH)

There is only one type of downlink dedicated physical channel the Downlink Dedicated Physical Channel (DL DPCH) Within one downlink DPCH dedicated data generated at Layer 2 and above ie the dedicated transport channel (DCH) is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits TPC commands and an optional TFCI)

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 81: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

81

Frame Structure of DL DPCH

One radio frame Tf = 10 ms

TPC NTPC bits

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 102k bits (k=07)

Data2Ndata2 bits

DPDCHTFCI

NTFCI bitsPilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 82: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

82

DL DPCH

ParametersEach frame= 15 slots = 10 ms

Each slot= 2560 chips

Each slot= one power-control period

SF = 5122k (eg SF=512 256 4)Two basic types

With TFCI (for several simultaneous services)Without TFCI (fixed-rate services)

It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the downlink

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 83: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

83

DL DPCH Fields (table is not completed)

8-14442822025615305A

154221022025615305

8-148042444012830604B

8-144021222025615304A

154021222025615304

8-144442444012830603B

8-142421022025615303A

152221222025615303

8-144042844012830602B

8-142021422025615302A

152021422025615302

8-14844402025615301B

15422201051275151

8-14804802025615300B

8-14402401051275150A

15402401051275150

NPilotNTFCINTPCNData2NData1

Transmittedslots per

radio frame NTr

DPCCHBitsSlot

DPDCHBitsSlot

Bits Slot

SFChannelSymbol

Rate (ksps)

ChanneBit Rate(kbps)

SlotFormat i

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 84: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

84

DL DPCH Pilot Bit Patterns

100000101101110011111010010001

111111111111111111111111111111

111110011101101000001100010010

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

101001000110000010110111001111

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

111111111111111111111111111111

110001001011111001110110100000

Slot 01234567891011121314

765432103210100Symbol

Npilot = 16(3)

Npilot = 8(2)

Npilot = 4(1)

Npilot=2

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 85: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

85

DL DPCH Multi-Code Transmission

TransmissionPower Physical Channel 1

TransmissionPower Physical Channel 2

TransmissionPower Physical Channel L

DPDCH

One Slot (2560 chips)

TFCI PilotTPC

bull bull

bull

DPDCH Condition

Total bit rate to be transmitted exceeds the maximum bit rate

Layer 1 control information is transmitted only on the first DL DPCH

Multicodetransmission is mapped onto several parallel downlink DPCHs using the same spreading factor

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 86: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

86

Common Pilot Channel (CPICH)Frame Structure

Pre-defined symbol sequence

Slot 0 Slot 1 Slot i Slot 14

Tslot = 2560 chips 20 bits = 10 symbols

1 radio frame Tf = 10 ms

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 87: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

87

Common Pilot Channel

The CPICH is a fixed rate (30 kbps SF=256) downlink physical channel that carries a pre-defined bitsymbol sequenceIn case transmit diversity (open or closed loop) is used on any downlink channel in the cell the CPICH shall be transmitted from both antennas using the same channelization and scrambling codeThere are two types of Common pilot channels

The Primary CPICHThe Secondary CPICH

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 88: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

88

Transmit Diversity of CPICHModulation pattern for Common Pilot Channel (with A = 1+j)

slot 1

Framei+1Framei

slot 14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot 0

Frame Boundary

In case of no transmit diversity thesymbol sequence of Antenna 1 is used

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 89: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

89

The Primary CPICHThe Primary Common Pilot Channel (P-CPICH) has the following characteristics

The same channelization code is always used for the P-CPICHThe P-CPICH is scrambled by the primary scrambling codeThere is one and only one P-CPICH per cellThe P-CPICH is broadcast over the entire cell

The Primary CPICH is a phase reference for the following downlink channels SCH Primary CCPCH AICH PICH AP-AICH CDCA-ICH CSICH DL-DPCCH for CPCH and the S-CCPCHBy default the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCHThe Primary CPICH is always a phase reference for a downlink physical channel using closed loop TX diversity

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 90: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

90

Secondary Common Pilot Channel(S-CPICH)

A Secondary Common Pilot Channel (S-CPICH) has the following characteristics

An arbitrary channelization code of SF=256 is used for the S-CPICHA S-CPICH is scrambled by either the primary or a secondary scrambling codeThere may be zero one or several S-CPICHs per cellA S-CPICH may be transmitted over the entire cell or only over a part of the cell

A Secondary CPICH may be a phase reference for a downlink DPCHThe Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX diversity instead of the Primary CPICH being a phase reference

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 91: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

91

Downlink Phase Reference

ndashndashˇDL-DPCCH for CPCH

ndashndashˇCSICH

ndashndashˇAICH

ˇˇˇPDSCH

ndashndashˇPICH

ˇˇˇDPCH

ndashndashˇS-CCPCH

ndashndashˇSCH

ndashndashˇP-CCPCH

Dedicated PilotSecondary-CPICHPrimary-CPICHPhysical Channel Type

Note the same phase reference as with the associated DPCH shall be used

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 92: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

92

Timing Relationship between Physical Channels

kth S-CCPCH

AICH access slots

Secondary SCH

Primary SCH

τS-CCPCHk

10 ms

τPICH

0 1 2 3 14 13 12 11 10 9 8 7 6 5 4

Radio frame with (SFN modulo 2) = 0 Radio frame with (SFN modulo 2) = 1

τDPCHn

P-CCPCH

Any CPICH

PICH for kth S-CCPCH

Any PDSCH

nth DPCH

10 ms

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 93: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

93

Spreading for All Downlink Physical Channels Except Synchronization Channel (SCH)

I

Any downlinkphysical channelexcept SCH

SrarrP

CchSFm

j

Sdln

Q

I+jQ S

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 94: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

94

Spreading and Modulation for SCH and P-CCPCH

Different downlink Physical channels (point S in Figure of previous page)

Σ

G1

G2

GP

GS

S-SCH

P-SCH

Σ

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 95: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

95

Downlink Scrambling Codes8192 codes are chosen from a total of 218-1 scrambling codes numbered 0hellip262142

These chosen scrambling codes are divided into 512 sets each set has

One primary scrambling codeCode number n=16i (i=0hellip511)

15 secondary scrambling codes Code number n=16i+k (k=1hellip15)

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 96: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

96

Downlink Scrambling Codes512 primary scrambling codes

Further divided into 64 scrambling code groups

Each group consisting of 8 primary scrambling codes

The jth scrambling code group consists of primary scrambling codes 168j+16k (j=063 amp k=07)

Each cell is allocated one and only one primary scrambling codeThe primary CCPCH primary CPICH PICH AICH AP-AICH CDCA-ICH CSICH and S-CCPCH carrying PCH are always transmitted using the primary scrambling codeThe other downlink physical channels can be transmitted with either the primary scrambling code or a secondary scrambling code from the set associated with the primary scrambling code of the cell

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 97: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

97

Configuration of Downlink Scrambling Code Generator

I

Q

1

1 0

02

2

3

3

4

4

5

5

6

6

7

7

8

8

9

9

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 98: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

98

Downlink Scrambling CodesConstructed by combining two real sequencesEach is constructed as the position wise modulo 2 sum of two binary m-sequences x and y

Generator polynomials is of degree 18

38400 chip segments (10 ms radio frame)

Gold sequences

x sequence generator polynomial 1+X7+X18

Initial x (0)=1 x(1)= x(2)== x (16)= x (17)=0

x(i+18) =x(i+7) + x(i) modulo 2 i=0hellip218-20

y sequence generator polynomial 1+y 5+y 7+ y 10+y 18

Initial y(0)=y(1)= hellip =y(16)= y(17)=1

y(i+18) = y(i+10)+y(i+7)+y(i+5)+y(i) modulo 2 i=0hellip 218-20

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 99: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

99

Downlink Scrambling Codes

The nth Gold code sequence zn iszn(i) = x((i+n) modulo (218 - 1)) + y(i) modulo 2 i=0hellip 218-2

Mapping

The nth complex scrambling code sequence Sdln is defined as

22101)(10)(1

)( 18 minus=⎩⎨⎧

=minus=+

= hellipiforizifizif

iZn

nn

Sdln(i) = Zn(i) + j Zn((i+131072) modulo (218-1)) i=01hellip38399

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 100: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

100

Downlink ModulationIn the downlink the complex-valued chip sequence generated by the spreading process is QPSK modulated

T

ImT

ReT

cos(ωt)

Complex-valuedchip sequencefrom summingoperations

-sin(ωt)

Splitreal ampimagparts

Pulse-shaping

Pulse-shaping

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus

Page 101: WCDMA FDD Mode Transmitter - 140.117.160.140140.117.160.140/.../9222/BBIC-1-WCDMAtransmitter.pdf · Introduction to WCDMA Transmitter Specifications ... The Radio Access Network (RAN,

101

Downlink Transmitter Functional Block

DI

DQ

jAntipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1 sum

Pulse Shaping

Filter

Pulse Shaping

Filter

sum

Root Nyquistr=022

Root Nyquistr=022

Channel Model

-Complex Gaussian

-MultipathRayleigh

-UMTS Channel

TSprimeTS+

+

+

+

Other User Signals

IC

IC

QC

ch1C

ch1C

DPDCH1DPCCH

Antipodal Conv

ldquo0rdquogt+1 ldquo1rdquogt-1

Gain Control

sum+

minus