wcdma demo presentation
DESCRIPTION
WCDMA Demo presentationTRANSCRIPT
WCDMA Demos PresentationThe MathWorks, Inc.
May 30th, 2002
You should here music now. If you do not, check that your PC speakers are on and you can play sounds on your computer.
© 2002 The MathWorks, Inc.
WCDMA stands for Wideband Code Division Multiple Access.
WCDMA is one of the five air-interfaces adopted by the ITU under the name "IMT-2000 Direct Spread”.
WCDMA can support multiple and simultaneous communications such as voice, images, data, and video.
Very high and variable bit rates:
144 kbps: vehicle speed, rural environ.
384 kbps: walking speed, urban outdoor.
2048 kbps: fixed, indoor.
High spectrum efficient.
Coexistence with current systems.
WCDMA is being specified by the 3GPP (Third Generation Partnership Project).
ITU-R (International Telecommunications Union Radio) Study Group 8
© 2002 The MathWorks, Inc.
References:
http://www.3gpp.org
http://www.uwcc.org
© 2002 The MathWorks, Inc.
TDD (Time Division Duplex).
FDD (Frequency Division Duplex).
Uplink Channel
Model simulates transmission of information data (DCH – Dedicated Channel) during a connection.
© 2002 The MathWorks, Inc.
w/o accelerator
WCDMA Library
WCDMA Multiplexing
and Coding
WCDMA Spreading
and Modulation
WCDMA Physical
Physical Layer Specifications
Physical layer provides data transport support to higher layers via Transport Channels.
Functions of the Physical Layer:
Error detection.
FEC encoding/decoding.
Rate Matching/Dematching.
Mapping/Demapping of CCTrCH into/from Physical Channels.
Modulation and Spreading/Demodulation and Despreading.
Power Weighting and combining of physical channels.
RF Processing.
Variables are stored in the workspace.
To view them, type who or whos
Multiplexing and Coding
Spreading and Modulation
© 2002 The MathWorks, Inc.
Coding and Multiplexing Specifications
Physical layer provides data transport support to higher layers via Transport Channels.
There is a Transport Format associated to each Transport Channel that describes the processing (CRC size, encoding scheme, coding rate, …) to be applied by the Physical Layer.
Every transport block is generated every 10, 20, 40 or 80 ms (Time Transmission Interval – TTI).
© 2002 The MathWorks, Inc.
Coding and Multiplexing Overview
Limits Max Size
Attaches CRC
Size={0,8,12,16,24}
One CCTrCH can be mapped onto one or several PhCHs
Slot
Builder
CCTrCh
DPCH
DPCH
TFCI
Interleaves bits within a Radio Frame coming from different Transport Channels
Transport Format Combination Index contains information of how the different transport channel have been processed
Data 1
Pilot
Structure of slot is defined by the Higher Layers via Slot Format
Data is sent to the Modulation and Spreading block
© 2002 The MathWorks, Inc.
Physical Channel Mapping Model
3GPP TS 25.302 – “Services provided by the Physical Layer”.
3GPP TS 25.211 – “Physical channels and mapping of transport channels onto Physical Channels (FDD)”.
3GPP TS 25.212 – “Multiplexing and channel coding”.
3GPP TS 25.944 – “Channel coding and multiplexing examples”.
© 2002 The MathWorks, Inc.
Modulation and Spreading Specifications
Spreading or Channelization Operation:
Transforms every bit into a given number of chips, hence increasing the bandwidth.
Chip Rate = 3.84 Mcps.
By using an orthogonal code for each physical channel, receiver can separate them.
Orthogonal codes are real-valued OVSF codes (Orthogonal Variable Spreading Factor) of different length.
Scrambling:
Power weighting:
Different power is applied to each physical channel before being added together.
Pulse shaping:
Bandwidth is 5MHz.
Dedicated Channel:
P-CPICH Primary Common Pilot Channel
Could be used at the receiver end for channel estimation, tracking
P-CCPCH Primary Common Control Physical Channel
SCH Synchronization Channel
Used mainly for cell search: slot and frame timing acquisition.
PICH Paging Indicator Channel
Simulates interference caused by other users or signals.
© 2002 The MathWorks, Inc.
Modulation and Spreading Overview
Physical Channels are added before being sent to Pulse Shaping
DPCH
Spreading
3GPP TS 25.101 – “UE Radio Transmission and Reception”.
3GPP TS 25.211 – “Physical channels and mapping of transport channels onto Physical Channels (FDD)”.
3GPP TS 25.213 – “Spreading and Modulation (FDD)”.
© 2002 The MathWorks, Inc.
Standard does not defined Receiver algorithms.
Although specifications has been defined in a such a way that a RAKE receiver will satisfy most of the cases.
RAKE receiver consists of several branches (RAKE Fingers) each of them assigned to a different receive paths, due to:
Diversity reception (“echoes”) : sum of attenuated and delayed versions of the transmitted signal.
Handoff.
The outputs of the different RAKE fingers are aligned in time and coherently combined.
Convert destructive interference into constructive interference.
© 2002 The MathWorks, Inc.
Receiver requires knowledge of channelization codes used by Data (Dedicated Physical Channel) and Pilot.
Channel Estimation
Low Pass filter is introduced is smooth noise estimates.
Data Derotation or Phase Correction
Using channel estimates data is phase corrected.
Current RAKE receiver assumes perfect carrier and timing synchronization.
© 2002 The MathWorks, Inc.
Fingers
To
Decoder
Pilot Sequence, Channelization and Scrambling Code are generated at the receiver
Pilot Reference
Paths are aligned and added coherently
Oversampled data
Channel Models
3GPP standard specifies minimum requirement tests under for different data rates under different propagation conditions:
Static Channel (AWGN)
Birth-Death Propagation Conditions
Channel models are implemented using a Configurable Subsystem.
© 2002 The MathWorks, Inc.
Channel Models
Use the mask of the demo, to select any predefined profile.
To define any multipath profile, use the option User Defined.
10.bin
© 2002 The MathWorks, Inc.
Visualizing the results
There is an intrinsic delay between transmission and reception of at least 2 TTI.
Simulink libraries contain several other types of displays such as eye diagrams, scatter plots or histograms.
Spreading and Modulation Demo
Multiplexing and Coding Demo
BER BLER (Syndrome Detector)
© 2002 The MathWorks, Inc.
Visualizing the results
To open and close the scopes, double-click on the switch icon
9.bin
Enhancements
Current model and library can be used as a baseline to test different algorithms such as:
Turbo coding
Power Control
Open Loop
Cell Search
Multi-user detection.
Viterbi and Turbo decoding
Fixed-point and floating-point
© 2002 The MathWorks, Inc.
May 30th, 2002
You should here music now. If you do not, check that your PC speakers are on and you can play sounds on your computer.
© 2002 The MathWorks, Inc.
WCDMA stands for Wideband Code Division Multiple Access.
WCDMA is one of the five air-interfaces adopted by the ITU under the name "IMT-2000 Direct Spread”.
WCDMA can support multiple and simultaneous communications such as voice, images, data, and video.
Very high and variable bit rates:
144 kbps: vehicle speed, rural environ.
384 kbps: walking speed, urban outdoor.
2048 kbps: fixed, indoor.
High spectrum efficient.
Coexistence with current systems.
WCDMA is being specified by the 3GPP (Third Generation Partnership Project).
ITU-R (International Telecommunications Union Radio) Study Group 8
© 2002 The MathWorks, Inc.
References:
http://www.3gpp.org
http://www.uwcc.org
© 2002 The MathWorks, Inc.
TDD (Time Division Duplex).
FDD (Frequency Division Duplex).
Uplink Channel
Model simulates transmission of information data (DCH – Dedicated Channel) during a connection.
© 2002 The MathWorks, Inc.
w/o accelerator
WCDMA Library
WCDMA Multiplexing
and Coding
WCDMA Spreading
and Modulation
WCDMA Physical
Physical Layer Specifications
Physical layer provides data transport support to higher layers via Transport Channels.
Functions of the Physical Layer:
Error detection.
FEC encoding/decoding.
Rate Matching/Dematching.
Mapping/Demapping of CCTrCH into/from Physical Channels.
Modulation and Spreading/Demodulation and Despreading.
Power Weighting and combining of physical channels.
RF Processing.
Variables are stored in the workspace.
To view them, type who or whos
Multiplexing and Coding
Spreading and Modulation
© 2002 The MathWorks, Inc.
Coding and Multiplexing Specifications
Physical layer provides data transport support to higher layers via Transport Channels.
There is a Transport Format associated to each Transport Channel that describes the processing (CRC size, encoding scheme, coding rate, …) to be applied by the Physical Layer.
Every transport block is generated every 10, 20, 40 or 80 ms (Time Transmission Interval – TTI).
© 2002 The MathWorks, Inc.
Coding and Multiplexing Overview
Limits Max Size
Attaches CRC
Size={0,8,12,16,24}
One CCTrCH can be mapped onto one or several PhCHs
Slot
Builder
CCTrCh
DPCH
DPCH
TFCI
Interleaves bits within a Radio Frame coming from different Transport Channels
Transport Format Combination Index contains information of how the different transport channel have been processed
Data 1
Pilot
Structure of slot is defined by the Higher Layers via Slot Format
Data is sent to the Modulation and Spreading block
© 2002 The MathWorks, Inc.
Physical Channel Mapping Model
3GPP TS 25.302 – “Services provided by the Physical Layer”.
3GPP TS 25.211 – “Physical channels and mapping of transport channels onto Physical Channels (FDD)”.
3GPP TS 25.212 – “Multiplexing and channel coding”.
3GPP TS 25.944 – “Channel coding and multiplexing examples”.
© 2002 The MathWorks, Inc.
Modulation and Spreading Specifications
Spreading or Channelization Operation:
Transforms every bit into a given number of chips, hence increasing the bandwidth.
Chip Rate = 3.84 Mcps.
By using an orthogonal code for each physical channel, receiver can separate them.
Orthogonal codes are real-valued OVSF codes (Orthogonal Variable Spreading Factor) of different length.
Scrambling:
Power weighting:
Different power is applied to each physical channel before being added together.
Pulse shaping:
Bandwidth is 5MHz.
Dedicated Channel:
P-CPICH Primary Common Pilot Channel
Could be used at the receiver end for channel estimation, tracking
P-CCPCH Primary Common Control Physical Channel
SCH Synchronization Channel
Used mainly for cell search: slot and frame timing acquisition.
PICH Paging Indicator Channel
Simulates interference caused by other users or signals.
© 2002 The MathWorks, Inc.
Modulation and Spreading Overview
Physical Channels are added before being sent to Pulse Shaping
DPCH
Spreading
3GPP TS 25.101 – “UE Radio Transmission and Reception”.
3GPP TS 25.211 – “Physical channels and mapping of transport channels onto Physical Channels (FDD)”.
3GPP TS 25.213 – “Spreading and Modulation (FDD)”.
© 2002 The MathWorks, Inc.
Standard does not defined Receiver algorithms.
Although specifications has been defined in a such a way that a RAKE receiver will satisfy most of the cases.
RAKE receiver consists of several branches (RAKE Fingers) each of them assigned to a different receive paths, due to:
Diversity reception (“echoes”) : sum of attenuated and delayed versions of the transmitted signal.
Handoff.
The outputs of the different RAKE fingers are aligned in time and coherently combined.
Convert destructive interference into constructive interference.
© 2002 The MathWorks, Inc.
Receiver requires knowledge of channelization codes used by Data (Dedicated Physical Channel) and Pilot.
Channel Estimation
Low Pass filter is introduced is smooth noise estimates.
Data Derotation or Phase Correction
Using channel estimates data is phase corrected.
Current RAKE receiver assumes perfect carrier and timing synchronization.
© 2002 The MathWorks, Inc.
Fingers
To
Decoder
Pilot Sequence, Channelization and Scrambling Code are generated at the receiver
Pilot Reference
Paths are aligned and added coherently
Oversampled data
Channel Models
3GPP standard specifies minimum requirement tests under for different data rates under different propagation conditions:
Static Channel (AWGN)
Birth-Death Propagation Conditions
Channel models are implemented using a Configurable Subsystem.
© 2002 The MathWorks, Inc.
Channel Models
Use the mask of the demo, to select any predefined profile.
To define any multipath profile, use the option User Defined.
10.bin
© 2002 The MathWorks, Inc.
Visualizing the results
There is an intrinsic delay between transmission and reception of at least 2 TTI.
Simulink libraries contain several other types of displays such as eye diagrams, scatter plots or histograms.
Spreading and Modulation Demo
Multiplexing and Coding Demo
BER BLER (Syndrome Detector)
© 2002 The MathWorks, Inc.
Visualizing the results
To open and close the scopes, double-click on the switch icon
9.bin
Enhancements
Current model and library can be used as a baseline to test different algorithms such as:
Turbo coding
Power Control
Open Loop
Cell Search
Multi-user detection.
Viterbi and Turbo decoding
Fixed-point and floating-point
© 2002 The MathWorks, Inc.