08 inter frequency handover

RAN Feature Description Table of Contents

Table of Contents

Chapter 8 Inter-Frequency Handover........................................................................................8-1

8.1 Introduction to Inter-Frequency Handover.......................................................................8-1

8.1.1 Definition...............................................................................................................8-1

8.1.2 Purposes...............................................................................................................8-1

8.1.3 Terms and abbreviations.......................................................................................8-1

8.2 Availability........................................................................................................................ 8-2

8.2.1 Network Elements Involved...................................................................................8-2

8.2.2 Software Releases................................................................................................8-3

8.3 Impact.............................................................................................................................. 8-3

8.3.1 On System Performance.......................................................................................8-3

8.3.2 On Other Features.................................................................................................8-3

8.4 Technical Description.......................................................................................................8-3

8.4.1 Inter-Frequency Handover Configuration Model....................................................8-3

8.4.2 Overview of Inter-Frequency Handover.................................................................8-5

8.4.3 Handover Procedure.............................................................................................8-6

8.4.4 Inter-Frequency Handover Measurement..............................................................8-7

8.4.5 Inter-Frequency Handover Decision and Execution............................................8-31

8.4.6 Signaling Procedure for Inter-Frequency Handover Within One RNC.................8-37

8.4.7 Signaling Procedure for Inter-Frequency Handover Between RNCs...................8-39

8.5 Capabilities....................................................................................................................8-41

8.6 Implementation..............................................................................................................8-41

8.6.1 Enabling Inter-Frequency Handover....................................................................8-41

8.6.2 Reconfiguring Inter-Frequency Handover Parameters........................................8-42

8.6.3 Disabling Inter-Frequency Handover...................................................................8-45

8.7 Maintenance Information................................................................................................8-45

8.7.1 MML Commands.................................................................................................8-45

8.7.2 Alarms.................................................................................................................8-46

8.7.3 Counters..............................................................................................................8-46

8.8 References..................................................................................................................... 8-46

Huawei Technologies Proprietary

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RAN Feature Description List of Figures

List of Figures

Figure 8-1 Inter-Frequency Handover configuration model (1).............................................8-4





Figure 8-6 The cell with highest CPICH RSCP in the latest measurement report is chosen to

handover...................................................................................................................... 8-33

Figure 8-7 Inter-frequency handover between NodeBs within an RNC...............................8-37

Figure 8-8 Signaling procedure for inter-frequency handover between NodeBs within an RNC

..................................................................................................................................... 8-38

Figure 8-9 Inter-frequency hard handover between RNCs.................................................8-39

Figure 8-10 Signaling procedure for inter-frequency hard handover between RNCs..........8-40


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RAN Feature Description Llist of Tables

List of Tables

Table 8-1 NEs required for inter-frequency handover............................................................8-2

Table 8-2 RAN products and related versions.......................................................................8-3

Table 8-3 Phases of inter-frequency handover......................................................................8-7

Table 8-4 Procedures for inter-frequency handover measurement and decision..................8-8

Table 8-5 Functions of events in inter-frequency handover.................................................8-10

Table 8-6 Recommended Thresholds for Event 2D/2F/2B/2C.............................................8-26

Table 8-7 Commands for reconfiguring RNC oriented inter-frequency handover parameters.8-

43

Table 8-8 Commands for reconfiguring cell oriented inter-frequency handover parameters. . .8-

43

Table 8-9 MML commands related to inter-frequency handover..........................................8-45

Table 8-10 Counters of inter-frequency handover...............................................................8-46


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RAN Feature Description Chapter 8 Inter-Frequency Handover

Chapter 8 Inter-Frequency Handover

8.1 Introduction to Inter-Frequency Handover

8.1.1 Definition

See section 7.1 "Introduction to Handover."

8.1.2 Purposes

Inter-frequency handover provides supplementary coverage in inter-frequency

networking cells to share the load.

8.1.3 Terms and abbreviations

I. Terms

Term Description

BE service Best effort service, that is, interactive service or background service

Ping-pong

effect

Frequent handovers between cells due to changes in signal quality

or improper parameter settings

Compressed

mode

In the compressed mode, some timeslots in one or more

continuous physical frames do not send data. This mode applies to

inter-frequency measurement.

II. Abbreviations

Abbreviation Full Spelling

3G 3rd Generation

3GPP 3rd Generation Partnership Project

ALCAP Access Link Control Application Part

BE Best Effort

CN Core Network

DL Downlink


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Abbreviation Full Spelling

DRNC Drift RNC

DS-CDMA Direct-Sequence Code Division Multiple Access

FDD Frequency Division Duplex

HO Handover

IE Information Element

MS Mobile Station

PC Power Control

RB Radio Bearer

RL Radio Link

RNC Radio Network Controller

RRM Radio Resource Management

SHO Soft HandOver

SIR Signal to Interference Ratio

SRNC Serving RNC

TPC Transmit Power Control

UL Uplink

UE User Equipment

UMTS Universal Mobile Telecommunications System

UTRAN UMTS Terrestrial Radio Access Network

WCDMA Wideband Code Division Multiple Access

8.2 Availability

8.2.1 Network Elements Involved

The realization of inter-frequency handover depends on the cooperation of the UE,

the NodeB, and the RNC. Table 8-1 shows the Network Elements (NEs) required for

inter-frequency handover.


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Table 8-1 NEs required for inter-frequency handover

UE NodeB RNCMSC

ServerMGW SGSN GGSN HLR

√ √ √ – – – – –

Note:

–: not required

√: required

Note:

This chapter describes only the availability of the NodeB and the RNC.

8.2.2 Software Releases

Table 8-2 describes the versions of the RAN products that support the inter-

frequency handover.

Table 8-2 RAN products and related versions

Product Version

RNC BSC6800 V100R002 and later releases

NodeB

DBS3000 V100R006 and later releases

BTS3812A V100R005 and later releases

BTS3812E V100R005 and later releases

BTS3806 V100R002 and later releases

8.3 Impact

8.3.1 On System Performance

One of the impacts to the system is compressed mode. Because the inter-frequency

handover is implemented in compressed mode, when there are too many users on

the verge of the cell, the system downlink capacity and the uplink coverage are

reduced.


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Another impact is the affection to the quality of service for time-delay-sensitive

services

since the fact that hard handover will introduce handover delay.

8.3.2 On Other Features

None.

8.4 Technical Description

8.4.1 Inter-Frequency Handover Configuration Model

The configuration model for Inter-Frequency Handover is as show in Figure 8-2,

Figure 8-3, Figure 8-4, Figure 8-5 and Figure 8-6.

CellClass

RadioClass

GlobalParaClass NeighbourClass

INTERFREQNCELL .Class

RNC

INTERFREQHOCOV .Class

INTERFREQHONCOV .Class

CELLINTERFREQHONCOV.Class

CELLINTERFREQHOCOV.Class

INTRAFREQHO.Class CELLINTRAFREQHO.Class

CMCF.Class CELLCMCF.Class

Figure 8-2 Inter-Frequency Handover configuration model (1)


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INTERFREQHOCOV .Class

Inter-freq CS target frequency trigger Ec/No THD

Inter-freq PS target frequency trigger Ec/No THD

Inter-freq CS target frequency trigger RSCP THD

Inter-freq PS target frequency trigger RSCP THD

Inter-freq CS Used frequency trigger Ec/No THD

Inter-freq PS Used frequency trigger Ec/No THD

Inter-freq CS Used frequency trigger RSCP THD

Inter-freq PS Used frequency trigger RSCP THD

2B hysteresis

2B event trigger delay time

Inter-frequency measure periodical rpt period

Inter-freq measure timer length

HHO event trigger delay time

Inter-freq handover min access RSCP THD

Inter-freq handover min access Ec/No THD

HHO hysteresis

Inter-frequency measure report mode

Inter-frequency measure quantity

Inter-frequency measure filter coeff

Weight for Used frequency

Inter-freq CS measure start Ec/No THD

Inter-freq PS measure start Ec/No THD

Inter-freq CS measure start RSCP THD

Inter-freq PS measure start RSCP THD

2D hysteresis

2D event trigger delay time

Inter-freq CS measure stop Ec/No THD

Inter-freq PS measure stop Ec/No THD

Inter-freq CS measure stop RSCP THD

Inter-freq PS measure stop RSCP THD

2F hysteresis

2F event trigger delay time

CELLINTERFREQHOCOV .Class


INTERFREQHONCOV.Class

Inter-frequency measure filter coeff

Inter-freq measure target frequency trigger Ec/No THD

2C hysteresis

2C event trigger delay time

Inter-freq measure timer length

CELLINTERFREQHONCOV.Class INTERFREQNCELL.Class

Cell offset

Blind handover flag

Blind handover Priority



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CELLINTRAFREQHO.Class

1F event absolute EcNo threshold

1F event absolute RSCP threshold

1F hysteresis

1F event trigger delay time

INTRAFREQHO.Class


CELLCMCF.Class

DL SF threshold

UL SF threshold

CMCF.Class


8.4.2 Overview of Inter-Frequency Handover

I. Handover Types

Based on handover triggering causes, inter-frequency handover includes the

following types:

Inter-frequency handover based on coverage

The UE might leave the coverage of the current frequency during the movement

of the UE. In this case, the RNC needs to trigger an inter-frequency handover

based on coverage to avoid call drop.

Inter-frequency handover based on load

To balance the loads between inter-frequency concentric cells, the RNC would

choose some UEs to do inter-frequency handover according to user and service

priorities.

Inter-frequency handover based on speed

When the Hierarchical Cell Structure (HCS) is used, cells are divided into

different layers according to their coverage. Marco cell corresponds to large

coverage and low priority and Micro cell corresponds to small coverage and high

priority. Inter-frequency handover can be triggered by UE speed estimation


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algorithm of the HCS. The UE with high speed is handed over to a cell with

larger coverage to reduce the frequency of handover, while the UE with low

speed is handed over to a cell with smaller coverage and larger capacity to

improve the system capacity. For detailed information, see chapter 20 HCS

Handover.

II. Handover Triggering Conditions

The inter-frequency handover triggering conditions are as follows:

Inter-frequency

Handover TypeTriggering Conditions

Handover based on

coverage

UE Reporting of event 2D or periodically measurement

reporting

When receiving event 1F, the RNC will decide to try a

blind handover to inter-frequency cell if a blind handover

neighboring cell is available.

Handover based on

load

Load could be shared by inter-frequency cells.

Estimation decision from Load Reshuffling (LDR)

Algorithm Module.

Handover based on

estimation decision of

the UE speed in HCS

Estimation decision of the UE speed in HCS

Blind handover triggered by 1F event is only used in specific wireless environment in

order to avoid call drop or influence of compressed mode. This also save inter-

frequency measurement time when inter frequency measurement report from the UE

could not be received by the RNC.

8.4.3 Handover Procedure

Inter-frequency handover procedure includes the following three phases:

2) Handover measurement

3) Handover decision

4) Handover execution

Table 8-1 describes the phases of different types of inter-frequency handovers.


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Table 8-1 Phases of inter-frequency handover

Phase

Inter-Frequency

Handover Based on

Coverage

Inter-Frequency

Handover Based on

Load

Inter-Frequency

Handover

Based on Speed

Handover

measurement

The UE reports event

2D. Then the RNC

enables the

compressed mode

and starts inter-

frequency

measurement.

Periodical reporting

mode or event

reporting mode can

be used.

When receiving event

1F, the RNC will

decide to try a blind

handover.

-

The HCS speed

estimation

algorithm initiates

a handover

procedure.

If the handover is

from a micro cell

to another macro

cell, and blind

handover

condition is

fulfilled, the RNC

performs blind

handover to the

target cell.

Otherwise, the

RNC enables the

compressed

mode and starts

inter-frequency

measurement.

Handover

decision

After UE reports event

2B, the RNC performs

handover decision.

Or the UE periodically

reports the inter-

frequency

measurement report,

and the RNC decides

the handover after

evaluation.

The RNC performs

load reshuffling

algorithm and then

performs blind

handover decision.

The UE reports

event 2C. Then

the RNC

performs

handover

decision.

Handover

execution

The RNC initiates a

handover procedure.

The RNC initiates a

blind handover to the

target cell.

The RNC initiates

a handover

procedure.


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8.4.4 Inter-Frequency Handover Measurement

I. Measurements Procedures

Table 8-2 describes the procedures for inter-frequency handover measurement.

Table 8-2 Procedures for inter-frequency handover measurement and decision

Handover type Measurements Procedures

Inter-frequency

handover based on

coverage

After receiving an event 2D report message, the RNC

performs the following procedures:

1) Decides an inter-frequency handover measurement

based on coverage.

2) Starts controlling periodical or event 2B triggered

measurement reporting.

The inter-frequency reporting mode can be event

reporting or periodical reporting, and this mode is

configured as Inter-frequency measure report mode.

3) Decides to initiate an inter-frequency handover based

on measurement reports from the UE.

If event 2F is received, the RNC will stop inter-frequency

handover measurement.

Inter-frequency

handover based on

load balancing

N/A

Inter-frequency

handover based on

HCS speed

estimation

The RNC starts the inter-frequency measurement or inter-

system measurement for a UE after the handover based on

HCS speed estimation is triggered.

After receiving a event 2C report message, the RNC

decides to initiate an inter-frequency handover.


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Parameter name Inter-frequency measure report mode

Parameter ID InterFreqReportMode

GUI range Periodical_ reporting, Event_trigger

Physical range& unit None.

Default value Periodical_reporting

Optional / Mandatory Optional

MML command ADD CELLINTERFREQHOCOV / MOD

CELLINTERFREQHOCOV / SET INTERFREQHOCOV

Description:

Inter-frequency measurement reporting mode. "Periodical_reporting" represents

periodical reporting mode. "Event_trigger" represents event-triggered reporting

mode.

The event 2B/2D/2F or periodical measurement in inter-frequency handover can use

CPICH Ec/N0 or RSCP as the measurement quantity. The parameter is configured as

Inter-frequency measure quantity. The event 2C only uses CPICH Ec/N0 as the

measurement quantity.

Parameter name Inter-frequency measure quantity

Parameter ID InterFreqMeasQuantity

GUI range CPICH_Ec/No, CPICH_RSCP

Physical range& unit None

Default value CPICH_RSCP




Description:

Measurement quantity used in coverage-based inter-frequency measurement in

event (2B/2D/2F)–triggered and periodical reporting modes.


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II. Measurement Model and L3 Filtering Coefficient

The model for inter-frequency measurement is the same as that for intra-frequency

measurement, for details, refer to corresponding part in intra-frequency handover.

The L3 filtering coefficient of the measurement value is configured as Inter-

frequency measure filter coeff, and the value is configured based on the type of the

inter-frequency handover. The frequency weighting factor used to calculate the

current frequency is configured as Weight for Used frequency.

Parameter name Inter-frequency measure filter coeff

Parameter ID InterFreqFilterCoef

GUI range D0, D1, D2, D3, D4, D5, D6, D7, D8, D9, D11, D13, D15,

D17, D19

Physical range& unit 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 15, 17, 19

Default value D3




Description:

L3 filtering coefficient for inter-frequency measurement. The greater this parameter

is, the greater the smoothing effect and the higher the anti fast fading capability,

but the lower the signal change tracing capability.


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Parameter name Inter-frequency measure filter coeff

Parameter ID InterFreqFilterCoef

GUI range D0, D1, D2, D3, D4, D5, D6, D7, D8, D9, D11, D13, D15,

D17, D19

Physical range& unit 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 15, 17, 19

Default value D3


MML command ADD CELLINTERFREQHONCOV / MOD

CELLINTERFREQHONCOV / SET

INTERFREQHONCOV

Description:

L3 filtering coefficient for inter-frequency measurement. The greater this parameter

is, the greater the smoothing effect and the higher the anti fast fading capability,

but the lower the signal change tracing capability.

Parameter name Weight for Used frequency

Parameter ID WeightForUsedFreq

GUI range 0–20

Physical range& unit 0–2; step: 0.1

Default value 0




Description:

Weight used for computing frequency general quality. The more this parameter is,

the higher the calculated general quality of an active set. When this parameter is 0,

the general quality of the active set is the quality of the best cell in it.

III. Measurement Events

Table 8-3 describes the functions of events in inter-frequency handover.


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Table 8-3 Functions of events in inter-frequency handover

Event Function

Event 2D

When the current signal quality is lower than the preset threshold, the

system enables the compressed mode and starts inter-frequency

measurement.

Event 2F

When the current signal quality is higher than the preset threshold, the

system disables the compressed mode and stops inter-frequency

measurement.

Event 2B

When the current signal frequency is lower than the preset threshold

and the signal quality of an inter-frequency neighboring cell is higher

than the preset threshold, the system triggers an inter-frequency

handover based on coverage.

Event 2CThe estimated quality of the cell that uses other frequency is higher

than the preset threshold.

IV. Triggering of Event 2D

Event 2D

Where,

QUsed is the measured quality of the cell that uses the current frequency.

TUsed2d is the absolute quality threshold of the cell that uses the current frequency.

Based on the service type (CS or PS) and measurement quantity (CPICH Ec/No

or RSCP), this threshold can be configured as Inter-freq CS measure start

Ec/No THD, Inter-freq PS measure start Ec/No THD, Inter-freq CS measure

start RSCP THD, Inter-freq PS measure start RSCP THD respectively.

H2d is the event 2D hysteresis value 2D hysteresis.

After the conditions of Event 2D are fulfilled and maintained until the 2D event trigger

delay time is reached, the UE reports the Event 2D measurement report message.


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Parameter name Inter-freq CS measure start Ec/No THD

Parameter ID InterFreqCSThd2DEcN0

GUI range –24–0

Physical range& unit –24–0 (dB)

Default value -16




Description:

If the CS service uses Ec/No as measurement item, when the measurement value

is lower than this threshold, the UE reports event 2D; the RNC sends a signaling to

enable compressed mode and start inter-frequency measurement.

Parameter name Inter-freq PS measure start Ec/No THD

Parameter ID InterFreqPSThd2DEcN0

GUI range –24–0


Default value -16




Description:

If the PS service uses Ec/No as measurement item, when the measurement value

is lower than this threshold, the UE reports event 2D; the RNC sends a signaling to



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Parameter name Inter-freq CS measure start RSCP THD

Parameter ID InterFreqCSThd2DRSCP

GUI range –115 to –25

Physical range& unit –115 to –25 (dBm)

Default value -95




Description:

If the CS service uses RSCP as measurement item, when the measurement value

is lower than this threshold, the UE reports event 2D; the RNC sends a signal to


Parameter name Inter-freq PS measure start RSCP THD

Parameter ID InterFreqPSThd2DRSCP



Default value -95




Description:

If the PS service uses RSCP as measurement item, when the measurement value

is lower than this threshold, the UE reports event 2D; the RNC sends a signal to



15


Parameter name 2D hysteresis

Parameter ID Hystfor2D

GUI range 0–29

Physical range& unit 0–14.5; step: 0.5 (dB)

Default value 6




Description:

Event 2D trigger hysteresis. This parameter value is related to the slow fading

characteristic. The greater this parameter is, the less the ping-pong effect and

misjudgment that can be caused. However, in this case, the event cannot be

triggered in time.

Parameter name 2D event trigger delay time

Parameter ID TrigTime2D

GUI range D0, D10, D20, D40, D60, D80, D100, D120, D160,

D200, D240, D320, D640, D1280, D2560, D5000

Physical range& unit 0, 10, 20, 40, 60, 80, 100, 120, 160, 200, 240, 320, 640,

1280, 2560, 5000 (ms)

Default value D640




Description:

Event 2D trigger delay time. This parameter value is related to the slow fading

characteristic. The greater this parameter is, the smaller the misjudgment

probability is, but the lower the speed of event response to measured signal

changes.


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V. Triggering of Event 2F

Event 2F

,

Where,


TUsed2fis the absolute quality threshold of the cell that uses the current frequency.


or RSCP), this threshold can be configured as Inter-freq CS measure stop

Ec/No THD, Inter-freq PS measure stop Ec/No THD, Inter-freq CS measure

stop RSCP THD, Inter-freq PS measure stop RSCP THD respectively.

H2f is the event 2F hysteresis value 2F hysteresis.

After the conditions of Event 2F are fulfilled and maintained until the 2F event trigger

delay time is reached, the UE reports the Event 2F measurement report message.

Parameter name Inter-freq CS measure stop Ec/No THD

Parameter ID InterFreqCSThd2FEcN0

GUI range –24–0


Default value -14




Description:

If the CS service uses Ec/No as measurement item, when the measurement value

is higher than this threshold, the UE reports event 2F; the RNC sends a signaling

to disable compressed mode and stop inter-frequency measurement.

Configuration Rule and Restriction:

(CS service Inter-freq measure start Ec/No threshold – 2D hysteresis / 2) < (CS

service Inter-freq measure stop Ec/No threshold + 2F hysteresis / 2)


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Parameter name Inter-freq PS measure stop Ec/No THD

Parameter ID InterFreqPSThd2FEcN0

GUI range –24–0


Default value -14




Description:

If the PS service uses Ec/No as measurement item, when the measurement value




(PS service Inter-freq measure start Ec/No threshold – 2D hysteresis / 2) < (PS

service Inter-freq measure stop Ec/No threshold + 2F hysteresis / 2)

Parameter name Inter-freq CS measure stop RSCP THD

Parameter ID InterFreqCSThd2FRSCP



Default value -90




Description:

If the CS service uses RSCP as measurement item, when the measurement

value is higher than this threshold, the UE reports event 2F; the RNC sends a

signal to disable compressed mode and stop inter-frequency measurement.


18



(CS service Inter-freq measure start RSCP threshold – 2D hysteresis / 2) < (CS

service Inter-freq measure stop RSCP threshold + 2F hysteresis / 2)

Parameter name Inter-freq PS measure stop RSCP THD

Parameter ID InterFreqPSThd2FRSCP



Default value -90




Description:

If the PS service uses RSCP as measurement item, when the measurement value




(PS service Inter-freq measure start RSCP threshold – 2D hysteresis / 2) < (PS

service Inter-freq measure stop RSCP threshold + 2F hysteresis / 2)


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Parameter name 2F hysteresis

Parameter ID Hystfor2F

GUI range 0–29


Default value 6




Description:

Event 2F trigger hysteresis. This parameter value is related to the slow fading



triggered in time.

Parameter name 2F event trigger delay time

Parameter ID TrigTime2F

GUI range D0, D10, D20, D40, D60, D80, D100, D120, D160, D200,

D240, D320, D640, D1280, D2560, D5000


1280, 2560, 5000 (ms)

Default value D640




Description:

Event 2F trigger delay time. This parameter value is related to the slow fading


probability, but the lower the speed of event response to measured signal

changes.


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VI. Triggering of Event 2B

Event 2B

, and

Where

QNoused is the measured quality of the cell that uses other frequency.

TNoused2b is the absolute quality threshold of the cell that uses other frequency.


or RSCP), this threshold can be configured as Inter-freq CS target frequency

trigger Ec/No THD, Inter-freq PS target frequency trigger Ec/No THD, Inter-

freq CS target frequency trigger RSCP THD, And Inter-freq PS target

frequency trigger RSCP THD respectively.


TUsed2d is the absolute quality threshold of the cell that uses the current frequency.


or RSCP), this threshold can be configured as Inter-freq CS measure start

Ec/No THD, Inter-freq PS measure start Ec/No THD, Inter-freq CS measure

start RSCP THD, Inter-freq PS measure start RSCP THD respectively.

H2b is the event 2B hysteresis value 2B hysteresis.

After the conditions of Event 2B are fulfilled and maintained until the 2B event trigger

delay time is reached, the UE reports the Event 2B measurement report message.

Parameter name Inter-freq CS target frequency trigger Ec/No THD

Parameter ID InterFreqCovHOCSThdEcN0

GUI range –24–0


Default value -16




Description:

If CS service inter-frequency handover uses the event-triggered reporting mode,

event 2B might be triggered when the Ec/No value of the target frequency is higher

than this threshold. In the periodical reporting mode, this parameter is used for

handover evaluation on the RNC side.


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Parameter name Inter-freq PS target frequency trigger Ec/No THD

Parameter ID InterFreqCovHOPSThdEcN0

GUI range –24–0


Default value -16




Description:

If PS service inter-frequency handover uses the event-triggered reporting mode,

event 2B might be triggered when the Ec/No value of the target frequency is higher



Parameter name Inter-freq CS target frequency trigger RSCP THD

Parameter ID InterFreqCovHOCSThdRSCP



Default value -95




Description:


event 2B might be triggered when the RSCP value of the target frequency is higher




22


Parameter name Inter-freq PS target frequency trigger RSCP THD

Parameter ID InterFreqCovHOPSThdRSCP



Default value -95




Description:


event 2B might be triggered when the RSCP value of the target frequency is higher



Parameter name Inter-freq CS Used frequency trigger Ec/No THD

Parameter ID IFHOUsedFreqCSThdEcN0

GUI range –24–0


Default value -16




Description:


event 2B might be triggered when the Ec/No value of the used frequency is lower

than this threshold. (Event 2B can be triggered only when the two necessary

conditions can be met at the same time.)


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Parameter name Inter-freq PS Used frequency trigger Ec/No THD

Parameter ID IFHOUsedFreqPSThdEcN0

GUI range –24–0


Default value -16




Description:

If service inter-frequency handover uses the event-triggered reporting mode, event

2B might be triggered when the Ec/No value of the used frequency is lower than

this threshold. (Event 2B can be triggered only when the two necessary conditions

can be met at the same time.)

Parameter name Inter-freq CS Used frequency trigger RSCP THD

Parameter ID IFHOUsedFreqCSThdRSCP



Default value -95




Description:


event 2B might be triggered when the RSCP value of the used frequency is lower




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Parameter name Inter-freq PS Used frequency trigger RSCP THD

Parameter ID IFHOUsedFreqPSThdRSCP



Default value -95




Description:


event 2B might be triggered when the RSCP value of the used frequency is lower



Parameter name 2B hysteresis

Parameter ID Hystfor2B

GUI range 0–29


Default value 6




Description:

Event 2B trigger hysteresis. This parameter value is related to the slow fading



triggered in time


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Parameter name 2B event trigger delay time

Parameter ID TrigTime2B


D240, D320, D640, D1280, D2560, D5000


1280, 2560, 5000 (ms)

Default value D640




Description:

Event 2B trigger delay time. This parameter value is related to the slow fading



changes.

VII. Triggering of Event 2C

Event 2C

Where,

QNoused is the measured quality of the cell that uses other frequency.

TNoused is the absolute quality threshold of the cell that uses other frequency.

Inter-freq measure target frequency trigger Ec/No THD.

H2c is the event 2C hysteresis value 2C hysteresis.

After the conditions of Event 2C are fulfilled and maintained until the 2C event trigger

delay time is reached, the UE reports the Event 2C measurement report message.


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Parameter name Inter-freq measure target frequency trigger Ec/No

THD

Parameter ID InterFreqCovHOThdEcN0

GUI range –24–0


Default value -16




INTERFREQHONCOV

Description:

When the Ec/No value of the target frequency is higher than this threshold, event

2C can be triggered.

Parameter name 2C hysteresis

Parameter ID Hystfor2C

GUI range 0–29


Default value 6




INTERFREQHONCOV

Description:

Event 2C trigger hysteresis. This parameter value is related to the slow fading



triggered in time


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Parameter name 2C event trigger delay time

Parameter ID TrigTime2C

GUI range D0, D10, D20, D40, D60, D80, D100, D120, D160,

D200, D240, D320, D640, D1280, D2560, D5000


1280, 2560, 5000 (ms)

Default value D640




INTERFREQHONCOV

Description:

Event 2C trigger delay time. This parameter value is related to the slow fading



changes.

VIII. Triggering of Event 1F

Event 1F is triggered on the basis of the following formula:

Where:

MOld is the measurement value of the cell that becomes worse

T1f is an absolute threshold. The threshold parameters for different intra-

frequency measurement quantity are set to 1F event absolute EcNo threshold,

1F event absolute RSCP threshold respectively.

H1f is 1F hysteresis, the hysteresis value of event 1F.

If the signal quality of a cell not in the active set is worse than T1f - H1f/2 for a certain

time 1F event trigger delay time, the UE reports event 1F.


28


Parameter name 1F event absolute EcNo threshold

Parameter ID INTRAABLTHDFOR1FECNO

GUI range -24 ~0

Physical range& unit -24 ~0; step: 1 (dB)

Default value -24


MML command SET INTRAFREQHO / ADD CELLINTRAFREQHO /

MOD CELLINTRAFREQHO

Description:

The absolute EcNo threshold of the event 1F.It is easier to trigger event 1F if the

value increases.It is harder to trigger event 1F if the value decreases.

Parameter name 1F event absolute RSCP threshold

Parameter ID INTRAABLTHDFOR1FRSCP

GUI range -115~25

Physical range& unit -115~25; step: 1 (dB)

Default value 8



MOD CELLINTRAFREQHO

Description:

The absolute RSCP threshold of the event 1F.It is easier to trigger event 1F if the

value increases.It is harder to trigger event 1F if the value decreases.


29


Parameter name 1F hysteresis

Parameter ID Hystfor1D

GUI range 0–15

Physical range & unit 0–7.5; step: 0.5 (dB)

Default value 8



MOD CELLINTRAFREQHO

Description:

The hysteresis value of the event 1D. This parameter value is related to the slow

fading characteristic. The greater this value is set, the less ping-pong effect and

misjudgment can be caused. However, in this case, the event cannot be triggered

in time.

Parameter name 1F event trigger delay time

Parameter ID TRIGTIME1F


D240, D320, D640, D1280, D2560, D5000


1280, 2560, 5000 (ms)

Default value D640



MOD CELLINTRAFREQHO

Description:

The trigger delay time of the event 1F. This parameter value is related to the slow

fading characteristic. The greater this parameter is set, the smaller the

misjudgment probability, but the lower the response speed of the event to the

measured signal changes.


30


IX. Thresholds Summary for Events

Table 8-4 Recommended Thresholds for Event 2D/2F/2B/2C

Event Parameter NameDefault

Value

Physical

ValueUnit

2D Inter-freq CS measure start Ec/No THD -16 -16 dB

Inter-freq PS measure start Ec/No THD -16 -16 dB

Inter-freq CS measure start RSCP THD -95 -95 dBm

Inter-freq PS measure start RSCP THD -95 -95 dBm

2D hysteresis 6 3 dB

2D event trigger delay time D640 640 ms

2F Inter-freq CS measure stop Ec/No THD -14 -14 dB

Inter-freq PS measure stop Ec/No THD -14 -14 dB

Inter-freq CS measure stop RSCP THD -90 -90 dBm

Inter-freq PS measure stop RSCP THD -90 -90 dBm

2F hysteresis 6 3 dB

2F event trigger delay time D640 640 ms

2BInter-freq CS target frequency trigger Ec/No

THD-16 -16 dB

Inter-freq PS target frequency trigger Ec/No

THD-16 -16 dB

Inter-freq CS target frequency trigger RSCP

THD-95 -95 dBm

Inter-freq PS target frequency trigger RSCP

THD-95 -95 dBm

Inter-freq CS Used frequency trigger Ec/No

THD-16 -16 dB

Inter-freq PS Used frequency trigger Ec/No

THD-16 -16 dB


31


Event Parameter NameDefault

Value

Physical

ValueUnit

Inter-freq CS Used frequency trigger RSCP

THD-95 -95 dBm

Inter-freq PS Used frequency trigger RSCP

THD-95 -95 dBm

2B hysteresis 6 3 dB

2B event trigger delay time D640 640 ms

2CInter-freq measure target frequency trigger

Ec/No THD-16 -16 dB

2C hysteresis 6 3 dB

2C event trigger delay time D640 640 ms

X. Periodical Measurement Reporting

The periodical report mode can be used in coverage-based inter-frequency handover

and is the recommended Inter-frequency measure report mode.

Based on the measurement control message sent by the RNC, the UE periodically

reports the measurement quality of the target cell on the basis of the configured

parameters Inter-frequency measure periodical rpt period and Inter-frequency

measure quantity, and then the RNC makes the handover decision based on the

measurement report and performs the handover procedure.

The advantage of periodical report is that, after the handover fails, the RNC retries

the handover to the same cell after receiving the periodical report from the UE, thus,

the success ratio of inter-frequency handover is improved.


32


Parameter name Inter-frequency measure periodical rpt period

Parameter ID PeriodReportInterval

GUI rangeNON_PERIODIC_REPORT,D250, D500, D1000,

D2000,D3000, D4000,D6000, D8000,D12000, D16000,

D20000, D24000, D28000, D32000, D64000

Physical range& unitNON_PERIODIC_REPORT,250, 500, 1000, 2000,3000,

4000,6000, 8000,12000, 16000, 20000, 24000, 28000,

32000, 64000 (ms)

Default value D500




Description:

Inter-frequency measurement reporting interval.

XI. Compressed Mode

In a WCDMA FDD system, the UE in CELL_DCH state sends and receives signals

continuously in uplink and downlink channels. If the UE in this case needs to measure

the pilot signal strength of an inter-frequency WCDMA or GSM cell, and it has only

mono-frequency receiver, the UE must use the compressed mode technique.

This technique increases the transmit capability of physical channel or reduces the

volume of data traffic. Thus, each physical frame can offer 3–7 timeslots for inter-

frequency or inter-RAT cell measurement.

Therefore, the compressed mode is usually used in inter-frequency or inter-RAT

handover. When the corresponding handover algorithm decides a measurement in

the compressed mode based on the capability of the UE, the RNC does as follows:

5) Sends parameters for the compressed mode to the NodeB and UE

6) Sets parameters for inter-frequency or inter-RAT cell measurement control

7) Activates the compressed mode

8) Update measurement control information to UE when needed

The radio network is affected when the UE performs the inter-frequency

measurement in compressed mode for a long time. To avoid this, the system stops

the inter-frequency measurement and disables the compressed mode if no inter-

frequency handover occurs upon expiry of the inter-frequency measurement timer

Inter-freq measure timer length.


33


This timer can be configured according to type of the inter-frequency handover, for

example, this timer can be configured as inter-frequency handover based on

coverage or inter-frequency handover based on non-coverage.

Parameter name Inter-freq measure timer length

Parameter ID InterFreqMeasTime

GUI range 0–512

Physical range& unit 0–512 (s)

Default value 60




Description:

If no inter-frequency handover occurs upon expiry of the inter-frequency

measurement timer, the system stops inter-frequency measurement and disables

the compressed mode if enabled. If this parameter is 0, the system will not start

the inter-frequency measurement timer.

Parameter name Inter-freq measure timer length

Parameter ID InterFreqMeasTime

GUI range 0–512

Physical range& unit 0–512 (s)

Default value 60




INTERFREQHONCOV

Description:

If no inter-frequency handover occurs upon expiry of the inter-frequency

measurement timer, the system stops inter-frequency measurement and disables

the compressed mode if enabled. If this parameter is 0, the system will not start

the inter-frequency measurement timer.


34


The compressed mode includes two types, spreading factor reduction (SF/2) and high

layer approaches. The usage of type of compressed mode is decided by the RNC

automatically, according to spreading factor used in uplink or downlink.

> When the downlink spreading factor is greater than or equal to this parameter

value, the SF/2 approach will be preferred. Otherwise, the high layer scheduing will

be preferred.

> When the uplink spreading factor is greater than or equal to this parameter value,

the SF/2 approach will be preferred. Otherwise, the high layer scheduling will be

preferred.

Parameter name DL SF threshold

Parameter ID DLSFTURNPOINT

GUI range D8, D16, D32, D64, D128, D256

Physical range& unit 8, 16, 32, 64, 128, 256

Default value D64


MML command SET CMCF / ADD CELLCMCF / MOD CELLCMCF

Description:

CM implementation approach selection basis. When the downlink spreading factor

is greater than or equal to this parameter value, the SF/2 approach will be

preferred. Otherwise, the high layer scheduing will be preferred.


35


Parameter name UL SF threshold

Parameter ID ULSFTURNPOINT

GUI range D8, D16, D32, D64, D128, D256

Physical range& unit 8, 16, 32, 64, 128, 256

Default value D64


MML command SET CMCF / ADD CELLCMCF / MOD CELLCMCF

Description:

CM implementation approach selection basis. When the uplink spreading factor is

greater than or equal to this parameter value, the SF/2 approach will be preferred.

Otherwise, the high layer scheduing will be preferred.

8.4.5 Inter-Frequency Handover Decision and Execution

I. Inter-frequency handover based on coverage - Periodical Reporting Mode

After receiving the periodical report of the inter-frequency cell, the RNC starts the

following decision process:

9) Decides whether the quality of the pilot signal of the target cell meet the

requirement of inter-frequency handover.

10) Starts the evaluation for the cells that meet the requirement of the handover and

runs the hard handover time-to-trigger timer.

11) Stops the evaluation of the cells whose quality is below the preset threshold and

stops the hard handover time-to-trigger timer.

12) Selects the cells in turn based on their quality from high to low to initiate inter-

frequency handover in all cells where the hard handover time-to-trigger timer is

timeout. The length of the hard handover time-to-trigger timer is configured as

HHO event trigger delay time.


36


Parameter name HHO event trigger delay time

Parameter ID TrigTimeHHO

GUI range 0–64000

Physical range& unit 0–64000 (ms)

Default value 640




Description:

Hard handover delay time of periodical reporting trigger.

After the RNC decides that the quality of an inter-frequency cell meets the

requirements, it starts the evaluation and run the hard handover time-to-trigger timer

in this cell. The requirements of inter-frequency handover consist of the following two

aspects:

The CPICH RSCP value and Ec/No value of the inter-frequency cell are both

higher than the minimum access threshold, that is the CPICH RSCP value is

higher than Inter-freq handover min access RSCP THD, and the Ec/No value

is higher than Inter-freq handover min access Ec/No THD.

The measured value of the inter-frequency cell is Mother_Freq + CIO

Tother_Freq + H/2

Where,

Mother_Freq is the CPICH measurement value of the target cell reported by the UE.

CIO is the Cell Individual Offset of the target cell Cell offset

Tother_Freq is the decision threshold for hard inter-frequency handover. Based on

the service type (CS or PS) and measurement quantity (CPICH Ec/No or RSCP),

this threshold can be configured as Inter-freq CS target frequency trigger

Ec/No THD, Inter-freq PS target frequency trigger Ec/No THD, Inter-freq CS

target frequency trigger RSCP THD, And Inter-freq PS target frequency

trigger RSCP THD respectively. This threshold is the same as the quality

threshold of the Event 2B target frequency cell.

H is the inter-frequency hard handover hystetesis value HHO hysteresis.

Bfore the hard handover time-to-trigger timer used for cell evaluation of inter-

frequency handover is overflow, the RNC stops the evaluation of the cell and stops

the hard handover time-to-trigger timer if it detects that the inter-frequency cell


37


measurement result periodically reported by the UE fulfils either of the following

conditions.

Either the CPICH RSCP value or the Ec/No value of the inter-frequency cell is

lower than the minimum threshold, that is the CPICH RSCP value is lower than

Inter-freq handover min access RSCP THD or the Ec/No value is lower than

Inter-freq handover min access Ec/No THD.

The measured value of the inter-frequency cell is Mother_Freq + CIO < Tother_Freq - H/2,

where, the parameters are the same as those when the evaluation is started.

There is an example to describe the procedure of evaluating the triggering of inter-

frequency handover.

When RNC receives inter-frequency measurement report form UE, RNC first

evaluates if there are cells full filled the requirements of handover threshold Inter-freq

CS target frequency trigger RSCP THD and hysteresis HHO hysteresis. If there

are, HHO event trigger delay time is started for each cell. If there is not, the timer

will not be started and just wait for the next measurement report.

For each cell in the measurement report, the above evaluation is performed. When

more than 1 cell’s HHO event trigger delay time expire at the same time, the latest

measurement report is used to choose the best inter-frequency cell to handover, i.e.

the cell with highest CPICH RSCP in the latest measurement report is chosen.

CPICH RSCP

InterFreqCovHoCsThdRSCP

HHOhysteresis

500 ms

StartIF

MR1 MR2 MR3 MR4 MR5

Timer for HHOevent trigger

delay time start

640 ms

HHO event triggerdelay time expire

and handover

Inter-frequencyneighbour cell1

t

Figure 8-1 The cell with highest CPICH RSCP in the latest measurement report is

chosen to handover


38


Parameter name Cell offset

Parameter ID CellIndividalOffset

GUI range -20–20

Physical range& unit -10–10; step: 0.5 (dB)

Default value 0


MML command ADD INTERFREQNCELL / MOD INTERFREQNCELL

Description:

Offset of cell CPICH measurement value. The sum of this parameter value and the

actual measured value is used in UE event evaluation. In handover algorithms, this

parameter is used for moving the border of a cell. It is configured according to the

actual environment.

Parameter name Inter-freq handover min access RSCP THD

Parameter ID HHORSCPmin



Default value -115




Description:

If the coverage-based inter-frequency uses the periodical reporting mode, a

handover to an inter-frequency cell might be allowed only when the RSCP value of

the cell is higher than this threshold.


39


Parameter name Inter-freq handover min access Ec/No THD

Parameter ID HHOEcNomin

GUI range –24–0


Default value -16




Description:

If the coverage-based inter-frequency uses the periodical reporting mode, a

handover to an inter-frequency cell might be allowed only when the Ec/No value of

the cell is higher than this threshold.

Parameter name HHO hysteresis

Parameter ID HystforHHO

GUI range 0–29


Default value 6




Description:

Hard handover hysteresis of periodical reporting trigger, used for inter-frequency


II. Inter-frequency handover based on coverage - Event Reporting Mode

After receiving the event 2B measurement report of the inter-frequency cell, the RNC

starts the following decision process:

Combines all the pilot cells that trigger the event 2B to a cell set and orders the

cells by the measurement quality from high to low.


40


Selects the cell in turn from the cell set to perform inter-frequency handover.

III. Inter-frequency based on coverage - Blind handover after Event 1F

After receiving 1F event of best cell from UE, the RNC would check if blind handover

target cell is configured for the best cell in the database, i.e. Blind handover flag and

Blind handover Priority.

If multiple blind handover target cells are configured, the RNC would perform blind

handover to the target cell with the highest priority Blind handover Priority.

To perform blind handover to the target cell, the RNC send PHYSICAL CHANNEL

RECONFIGURATION message to the UE.

Parameter name Blind handover flag

Parameter ID BLINDHOFLAG

GUI range FALSE, TRUE

Physical range& unit FALSE, TRUE

Default value FALSE


MML command ADD INTERFREQNCELL

Description:

Indicating whether to perform blind handover.

Parameter name Blind handover Priority

Parameter ID BLINDHOPRIO

GUI range 0~30

Physical range& unit 0~30

Default value None


MML command ADD INTERFREQNCELL

Description:

The value 0 represents the highest priority. The value range corresponds to only

one cell.


41


IV. Inter-frequency handover based on HCS speed estimation

If the handover is from a micro cell to a macro cell, and blind handover condition is

fulfilled, the RNC performs blind handover to the target cell.

If the inter-frequency measurement mode is employed, the RNC starts the inter-

frequency procedure for the cell with best quality in the target cells after receiving the

event 2C from the UE.

V. Inter-frequency handover based on load

The inter-frequency handover based on load is triggered by the LDR module. The

LDR module provides the target cell information for the current cell, and the RNC

performs the handover procedure.

8.4.6 Signaling Procedure for Inter-Frequency Handover Within One RNC

Figure 8-2 shows the inter-frequency handover when a UE moves from NodeB 1 to

NodeB 2 within an RNC.

CN

SRNC

NodeB1 NodeB2 NodeB1 NodeB2

CN

SRNC

(1) (2)

Figure 8-2 Inter-frequency handover between NodeBs within an RNC

Before the handover, the UE sets up a connection to NodeB 1. After the handover, the

UE sets up a connection to NodeB 2.

Figure 8-3 shows the signaling procedure for inter-frequency handover between

NodeBs within an RNC.


42


1. Radio Link Setup Request

2. Radio Link Setup Response

UE

NodeB2

SRNC

NodeB1

Decision to setup newRL

Decision to delete oldRL

8. Radio Link DeletionRequest

9.Radio Link Deletion Response

Stop RX andTX

4.Downlink Synchronization

5.Uplink Synchronization

UE NodeB2 SRNC NodeB1

Decision to setup new RL

Decision to delete old RL

Stop RX and TX

Start RX

Start TX

3. ALCAP Iub Data Transport Bearer Setup

10.ALCAP Iub Data Transport Bearer Release

6. DCCH : Physical Channel Reconfiguration

7. DCCH : Physical Channel Reconfiguration Complete

Figure 8-3 Signaling procedure for inter-frequency handover between NodeBs within

an RNC

As shown in Figure 8-3, NodeB 1 is the source NodeB and NodeB 2 is the target

NodeB. In steps 1–7, a new connection is set up. In steps 8–10, the old connection is

released.

The procedure is as follows:

1) SRNC decides to set up a radio link in a cell of NodeB 2, and sends a Radio Link

Setup Request message to NodeB 2.

2) NodeB 2 configures its physical channel and starts to receive UE signals for UL

synchronization, and then sends a Radio Link Setup Response message to the

DRNC.

3) DRNC sets up an ALCAP Iub Data Transport Bearer to bear the new connection

between the SRNC and NodeB 2.

4) SRNC sends a Downlink Synchronization frame to NodeB 2 through the new

bearer.


43


5) NodeB 2 sends an Uplink Synchronization frame to the SRNC through the new

bearer. NodeB 2 starts downlink transmission

6) SRNC sends an RRC message Physical Channel Reconfiguration to the UE

through DCCH.

7) UE responds with an RRC Physical Channel Reconfiguration Complete.

8) SRNC sends an NBAP message Radio Link Deletion Request to NodeB 1.

NodeB 1 stops uplink reception and downlink transmission.

9) NodeB 1 releases radio resources and then sends an NBAP message Radio

Link Deletion Response.

10) SRNC initiates the release of the ALCAP Iub Data Transport Bearer through

ALCAP protocol.

8.4.7 Signaling Procedure for Inter-Frequency Handover Between RNCs

Figure 8-1 shows the procedure for inter-frequency hard handover when a UE moves

from a NodeB to another NodeB between RNCs.

(1) (2)

CN

NodeB1 NodeB2

SRNC DRNC

CN

NodeB1 NodeB2

SRNC DRNC

Figure 8-1 Inter-frequency hard handover between RNCs

Before the handover, the UE sets up a connection to NodeB 1. After the handover, the

UE sets up a connection to NodeB 2.

Figure 8-2 shows the signaling procedure for inter-frequency handover between

RNCs.


44


UE NodeB2 DRNC SRNC NodeB1

Decision to setup new Radio Link

1.Radio Link Setup

Requset2.Radio Link Setup Requset

Start Rx

3.Radio Link SetupResponse

Response

4.Radio Link Setup

5. ALCAP Iub Data Transport Bearer Setup

6. ALCAP Iur Data Transport Bearer Setup

7.Radio Link Restore

Indicate8.Radio Link

Restore Indicate

9. Downlink Synchronization

Start Tx

11. DCCH: Physical Channel Reconfiguration

10. Uplink Synchronization

12. DCCH: Physical Channel Reconfiguration Complete13. Radio Link Deletion

Request

Stop Rx and Tx

14. Radio Link DeletionResponse

15.ALCAP Iub Data Transport Bearer Release

Figure 8-2 Signaling procedure for inter-frequency hard handover between RNCs

As shown in Figure 8-2, NodeB 1 is the source NodeB and NodeB 2 is the target

NodeB. In steps 1–12, a new connection is set up. In steps 12–15, the old connection

is released.

The procedures are as follows:

1) SRNC decides to set up a radio link in a cell of NodeB 2, and sends a Radio Link

Setup Request message to NRNC.

2) DRNC forwards this Radio Link Setup Request message to NodeB2.

3) NodeB 2 configures its physical channel and starts to receive UE signals for UL

synchronization, and then sends a Radio Link Setup Response message to the

DRNC.


45


4) DRNC sends the Radio Link Setup Response message to SRNC.

5) SRNC sets up an ALCAP Iub Data Transport Bearerto bear the new

connectection between NodeB2.

6) SRNC sets up and ALCAP Iur Data Transport Bearer between DRNC.

7) NodeB2 sends an Radio Link Restore Indicate message to DRNC.

8) DRNC sends the Radio Link Restore Indicate message to SRNC.

9) SRNC sends a Downlink Synchronization message to NodeB2.

10) NodeB2 sends a Uplink Synchronization message to SRNC, and NodeB2 starts

downlink transmission.

11) SRNC sends a RRC message Physical Channel Reconfiguration to UE through

DCCH.

12) UE responds the RRC message with a Physical Channel Reconfiguration

Complete message.

13) SRNC sends a NBAP message Radio Link Deletion Request to NodeB1,

NodeB1 stops the uplink receving and downlink transmiting.

14) NodeB1 releases radio resources, and reports the success of the release

through an NBAP message Radio Link Deletion Response.

15) SRNC initiates the release of the Iub Data Transport Bearer through the ALCAP.

8.5 Capabilities

None.

8.6 Implementation

8.6.1 Enabling Inter-Frequency Handover

I. Hardware Installation

This feature does not need extra hardware.

II. Software Installation

This feature does not need extra software.

III. License Update

This feature does no need license.

IV. Data Configuration

To configure the parameters for the inter-frequency handover, perform the following

steps:

16) Execute the ADD INTERFREQNCELL command to ADD INTER-frequency

neighboring cell.


46


17) Execute the SET CORRMALGOSWITCH command to turn on inter-frequency

handover switch.

18) Execute the LST INTERFREQHOCOV command to query whether RNC

oriented inter-frequency handover parameters are reasonable. If RNC oriented

inter-frequency handover measurement algorithm parameters need to be

reconfigured, execute the SET INTERFREQHOCOV command.

V. Verification of the Enabled Feature

To verify the enabled inter-frequency handover, perform the following step:

1) Execute the LST INTERFREQNCELL command to query whether the inter-

frequency neighboring cell is configured.

2) Execute the LST CORRMALGOSWITCH command to query whether the state

of the parameters active set quality measurement switch and inter-frequency

handover algorithm switch are ON.

3) If the ADD CELLINTERFREQHOCOV is executed to configure cell oriented

parameters, then, Execute the LST CELLINTERFREQHOCOV command to

query whether the configured cell oriented inter-frequency handover parameters

are reasonable. If not reasonable, Execute the LST INTERFREQHOCOV

command to query RNC oriented inter-frequency handover parameters.

VI. Examples

// (1) Set cell 100 of RNC 9 as an inter-frequency neighboring cell of cell 1.

ADD INTERFREQNCELL: CELLID=1, RNCID=9, NCELLID=100,

READSFNIND=NOT_READ, CELLINDIVIDALOFFSET=0, QOFFSET1SN=0,

QOFFSET2SN=0, TPENALTYHCSRESELECT=D0, BLINDHOFLAG=FALSE;

// (2) Enable the RNC-oriented inter-frequency handover algorithm.

SET CORRMALGOSWITCH:

HOSWITCH=ACT_SET_QUAL_SWITCH-1&INTER_FREQ_HHO_SWITCH-1;

8.6.2 Reconfiguring Inter-Frequency Handover Parameters

I. Parameter Reconfiguration on the RNC Side

The commands for reconfiguring inter-frequency handover parameters on RNC side

fall into the following two categories:

Table 8-1 shows the commands for reconfiguring RNC oriented inter-frequency

handover parameters.

Table 8-2 shows the commands for reconfiguring cell oriented inter-frequency

handover parameters.


47


Table 8-1 Commands for reconfiguring RNC oriented inter-frequency handover

parameters

Function Command

List RNC oriented connection algorithm switch

parameterLST CORRMALGOSWITCH

Set RNC oriented connection algorithm switch

parameterSET CORRMALGOSWITCH

List RNC oriented coverage-based inter-frequency

handover measurement algorithm parameterLST INTERFREQHOCOV

Set RNC oriented coverage-based inter-frequency

handover measurement algorithm parameterSET INTERFREQHOCOV

Table 8-2 Commands for reconfiguring cell oriented inter-frequency handover

parameters

Function Command

ADD INTER-frequency neighboring cell ADD INTERFREQNCELL

Modify inter-frequency neighboring cell MOD INTERFREQNCELL

List inter-frequency neighboring cell LST INTERFREQNCELL

Remove inter-frequency neighboring cell RMV INTERFREQNCELL

Add cell oriented coverage-based inter-

frequency handover measurement algorithm

parameter

ADD CELLINTERFREQHOCOV

Modify cell oriented coverage-based inter-


parameter

MOD CELLINTERFREQHOCOV

List cell oriented coverage-based inter-


parameter

LST CELLINTERFREQHOCOV

Remove cell oriented coverage-based inter-


parameter

RMV CELLINTERFREQHOCOV


48


II. Parameter Reconfiguration on the NodeB Side

None.

III. Parameter Reconfiguration Verification

Execute the LST INTERFREQHOCOV command to query RNC oriented inter-

frequency handover parameter.

IV. Examples

//Reconfigure RNC oriented coverage-based inter-frequency measurement

algorithm parameters.

//(1)List RNC oriented coverage-based inter-frequency measurement


LST INTERFREQHOCOV:;

//(2)Set RNC oriented coverage-based inter-frequency measurement algorithm

parameters.

SET INTERFREQHOCOV: INTERFREQFILTERCOEF=D6, PERIODREPORTINTERVAL=D8000;

//(3)Execute the LST INTERFREQHOCOV command to query whether RNC oriented

coverage-based inter-frequency measurement algorithm parameters are

reconfigured.

LST INTERFREQHOCOV:;

//The output results show that parameters are reconfigured.

//Reconfigure cell oriented coverage-based inter-frequency measurement


//(1)List cell oriented coverage-based inter-frequency measurement


LST CELLINTERFREQHOCOV: CellId=10101, LstFormat=VERTICAL;

//The output results show that cell parameters do not exist.

//(2)Add cell oriented coverage-based inter-frequency measurement


ADD CELLINTERFREQHOCOV: CellId=10101,

InterFreqReportMode=PERIODICAL_REPORTING,

InterFreqMeasQuantity=CPICH_RSCP, InterFreqFilterCoef=D3,

PeriodReportInterval=D500, Hystfor2B=6, Hystfor2D=6, Hystfor2F=6,

HystforHHO=6, WeightForUsedFreq=0, TrigTime2B=D640, TrigTime2D=D640,

TrigTime2F=D640, TrigTimeHHO=640, InterFreqCSThd2DEcN0=-16,

InterFreqCSThd2FEcN0=-14, InterFreqPSThd2DEcN0=-16, InterFreqPSThd2FEcN0=-

14, InterFreqCSThd2DRSCP=-95, InterFreqCSThd2FRSCP=-90,

InterFreqPSThd2DRSCP=-95, InterFreqPSThd2FRSCP=-90,

InterFreqCovHOCSThdEcN0=-16, InterFreqCovHOPSThdEcN0=-16,

InterFreqCovHOCSThdRSCP=-90, InterFreqCovHOPSThdRSCP=-90,

IFHOUsedFreqCSThdEcN0=-16, IFHOUsedFreqPSThdEcN0=-16,


49


IFHOUsedFreqCSThdRSCP=-95, IFHOUsedFreqPSThdRSCP=-95, HHOEcNomin=-16,

HHORSCPmin=-115, InterFreqMeasTime=60;

//(3)Execute the LST CELLHSSCCH command to query whether cell oriented

coverage-based inter-frequency measurement algorithm parameters are

reconfigured.

LST CELLINTERFREQHOCOV: CellId=10101, LstFormat=VERTICAL;

//The output results show that the parameters are reconfigured.

8.6.3 Disabling Inter-Frequency Handover

I. Method of Disabling Inter-Frequency Handover

Execute the SET CORRMALGOSWITCH command to turn off RNC oriented inter-

frequency handover switch.

Note that the disabling operation is only applicable to RNC. This operation is not

applicable to cell or NodeB.

II. Verification of the Disabled Feature

Execute the LST CORRMALGOSWITCH command to query the current state of the

algorithm switch. The disabling of inter-frequency handover in RNC succeeds when

the state of the inter-frequency hard handover switch is OFF.

III. Examples

//(1)Turn off inter-frequency handover algorithm switch

SET CORRMALGOSWITCH: HoSwitch=INTER_FREQ_HHO_SWITCH-0;

//(2)Execute the LST CORRMALGOSWITCH command to query whether inter-

frequency handover in RNC is disabled

LST CORRMALGOSWITCH: LstFormat=VERTICAL;

//The output results show that the state of inter-frequency hard handover

switch is OFF.

8.7 Maintenance Information

8.7.1 MML Commands

Table 8-3 shows the commands.

Table 8-3 MML commands related to inter-frequency handover

Command Description

SET CORRMALGOSWITCH Set inter-frequency handover algorithm switch

ADD INTERFREQNCELL ADD INTER-frequency neighboring cell


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Command Description

SET INTERFREQHOCOV

Set RNC oriented coverage-based inter-


parameter

MOD CELLINTERFREQHOCOV

Set cell oriented coverage-based inter-


parameter

SET HCSHOSet RNC oriented HCS hierarchical cell

parameter

ADD CELLHCSHOAdd cell oriented HCS hierarchical cell

parameter

8.7.2 Alarms

None.

8.7.3 Counters

Table 8-4 lists the counters of inter-frequency handover.

Table 8-4 Counters of inter-frequency handover

Counter Description Measurement Unit

VS.HHO.Att.RNCNumber of Hard Handover

RequestsHHO.RNC

VS.HHO.Succ.RNCNumber of Successful Hard

HandoversHHO.RNC

VS.HHO.InterFreq.AttOut

Number of Requested

Outgoing Inter-frequency

Handovers

HHO.CELL

VS.HHO.InterFreq.SuccOut

Number of Successful

Outgoing Inter-frequency

Handovers

HHO.CELL

VS.HHO.InterFreqIn.Att

Number of Requested

Incoming Inter-frequency

Handovers

HHO.CELL


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VS.HHO.InterFreqIn.Succ

Number of Successful

Incoming Inter-frequency

Handovers

HHO.CELL

8.8 References

3GPP, 25.331 "RRC Protocol Specification"

3GPP, 25.931 " UTRAN Functions, Examples on Signalling Procedures"


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08 inter frequency handover

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