05_RN20115EN20GLN0_ISHO

1 Nokia Siemens Networks RN20115EN20GLN0

BSSPAR2: GSM-WCDMA Inter System Handover


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Module Objectives

Explain feature activation, defining WCDMA adjacent cells and managed object class ADJW

Explain the features around GSM-WCDMA cell reselection procedure, like:

- Standard procedure (for Idle, Packet Idle and Packet Transfer modes)

- GSM to WCDMA advanced cell reselection (S13)

- Mobile specific channel release message (S13)

- IS-NCCR

Explain the features around GSM-WCDMA handover procedure, like:

- Load based ISHO for voice

- Coverage based ISHO for voice (S13)

- ISHO penalties and timers

- Inter-system direct access

- WCDMA neighbor cell reporting enhancement (S13)


GSM-WCDMA RAN Network Architecture


GSM WCDMA Interworking Benefits

Continuity of speech connections:

Dual mode UEs can have seamless continuity of speech connections and certain data services between WCDMA RAN and GSM networks

Handovers to reduce traffic load:

GSM BSS WCDMA handovers: To reduce traffic load in the GSM network (where networks overlap)

Handovers to extend network coverage:

WCDMA GSM BSS handovers: Provide a seamless coverage in areas where WCDMA RAN is not available

GSM BSS WCDMA handovers: To provide a seamless coverage in areas where GSM is not available

GSM GSM GSM GSM

WCDMA WCDMA


MS has to camp on a cell to get service from radio network A cell re-selection procedure ensures that the MS is camped on a cell

from which it can reliably decode downlink data and with which it has a high probability of communications on uplink

Cell re-selection procedure is used in Idle mode Packet idle mode Packet transfer mode

Dual-mode mobile can perform cell re-selection from GERAN to UTRAN FDD cell

GSM coverage area ends (default 2G camping) UMTS coverage area starts (default 3G camping) Better UTRAN FDD cell available according the cell re-selection

parameters

GSM WCDMA Interworking Cell Re-selection


Inter System Handover (ISHO) procedure is used for dual-mode mobiles in dedicated mode to offer seamless service between the radio access technologies

Inter System Network Controlled Cell Reselection (IS-NCCR) procedure is used for dual-mode mobiles in packet transfer mode to offer seamless service between the radio access technologies

BSC can start ISHO (or IS-NCCR) procedure from GERAN to UTRAN FDD cell when

GSM coverage area ends UMTS coverage area starts Better or less loaded UTRAN FDD cell is available according the

handover control parameters

BSC needs measurement results concerning the neighbor UTRAN FDD cells to able to make decision to start ISHO or IS-NCCR

GSM WCDMA Interworking ISHO and IS-NCCR


GSM WCDMA Interworking Feature Control

Support for CS and PS

ISHO feature is required to accept incoming inter system handovers as well (WCDMA to GSM)

The inter-system handover from GSM to WCDMA is initiated by the GSM radio network, and the inter-system handover from WCDMA to GSM is initiated by the WCDMA radio network

Inter-system handovers are hard handovers, which means that an inter-system handover causes a temporary disconnection of the real time (RT) radio access bearer

Standard Feature (activate by FIFILE parameter)

GSM-WCDMA Inter-System Handover (ISHO)

Licence Based

GSM-WCDMA Inter-System Direct Access

CPICH RSCP Based Criterion for 2G to 3G Cell Reselection

WCDMA Neighbour Cell Reporting Enhancement

Mobile Specific Channel Release Message

Coverage Based ISHO in Dedicated Mode

Inter-System Network Controlled Cell Reselection (IS-NCCR)


GSM to WCDMA Advanced Cell Reselection

Received signal code power (RSCP) can be used as an additional 2G to 3G cell re-

selection criterion in idle mode to prevent ping-pong effect in 2G-3G cell reselection


Received signal code power (RSCP) can be used as an additional 2G to 3G cell

handover criterion in dedicated mode to prevent ISHOs and IS-NCCRs from 2G to 3G

cell when the new cells uplink performance would be poor


To remove unnecessary signaling and to reduce the delay in service access, 3GPP

Rel.6 terminals can be commanded to directly camp to a 3G cell after call release in 2G

Service Quality Based WCDMA Access is a set of functionalities to further enhance the best in class BSS/RAN interworking performance

Service Quality Based WCDMA Access Enhancements in S13


Defining adjacent WCDMA cells

WCDMA adjacencies are defined in MO class ADJW (GSM adjacencies are in ADCE)

The maximum number of neighbour WCDMA RAN cells per a serving cell is limited to 32

If GSM-WCDMA ISHO is in use, the maximum number of neighbour GSM cells (ADJC) and maximum number of frequencies in BCCH Allocation (BA) list per a serving cell (or segment) are:

31 without Common BCCH Control

30 if Common BCCH Control is activated

GSM GSM

WCDMA

ADCE

ADJW


Defining adjacent WCDMA cells Parameters

MO

Class

Abbreviated

Name

Range And Step Description Default

value

BSC - MML

Name

ADJW scramblingCode 0...511, step 1 The downlink scrambling code of the

primary common pilot channel of the

adjacent WCDMA RAN cell

SCC

ADJW txDiversityInd Y, N Defines the downlink transmission diversity

capability of the logical node that is

controlling the adjacent UTRAN cell is used

or not.

N DIV

ADJW uarfcn 0...16383, step 1 Defines the downlink carrier frequency of

the adjacent UTRAN cell specified as its

UARFCN

FREQ


WCDMA Adjacent Cell Measurements

List of WCDMA neighbour cells is send on SI2 quarter on the downlink

The adjacent cell information is repeated for every neighbour WCDMA RAN cell:

WCDMA downlink carrier frequency

downlink transmission diversity

scrambling code

Dual mode GSM/WCDMA mobile must measure and report the neighboring WCDMA cells. The MS needs to be triggerred to start measurements (will not measure all the time on its own)

The cell re-selection parameters that are sent on SI 2quater messages are:

threshold to search WCDMA RAN cells (qSearchI, qSearchP for GPRS attached mobiles)

minimum fdd threshold (FddQmin)

fdd cell reselect offset (FddQoffset)


Re-selection measurements are controlled by parameter threshold to search WCDMA RAN cells (QSRI)

This parameter defines a threshold and also indicates whether these measurements are performed when RLA_C (a running average of received signal level) of the serving GSM cell is below or above the threshold

UE starts WCDMA measurements if Rxlev running average (RLA_C) is below or above

certain threshold: RLA_C Qsearch_I and Qsearch_P (GPRS)

WCDMA Measurement Triggering

In GSM the UE is usually set to measure the 3G neighbours all the time i.e. Qsearch_I

and Qsearch_P are both set to 7


WCDMA Measurement Triggering Parameters

Qsearch_I and Qsearch_P define the threshold for non-GPRS/GPRS (respectively) capable UEs to measure 3G neighbour cells when a running average of the received downlink signal level (RLA_C) of the serving cell is below (0-7) or above (8-15) the threshold

Value 0 1 6 7 8 9 10 14 15

dBm -98 -94 -74 Always -78 -74 -70 -54 Never

If RLA_C < -94 UE starts 3G measurements

UE always measures 3G cells If RLA_C > -70 UE starts 3G

measurements

Qsearch_C is used in case of dedicated mode and works the same way as above


WCDMA Measurement Triggering Idle mode parameters

MO

Class

Abbreviate

d Name

Description BSC - MML

Name

BTS qSearchI Defines the threshold for dual mode mobiles in

idle state to search for and to measure UTRAN

neighbour cells introduced in 3G Cell

Reselection list when a running average of the

received downlink signal level (RLA_C) of the

serving cell is below (0-7) or above (8-15) the

threshold. This parameter is broadcast only on

BCCH.

GPRS MS use this if IS-NCCR is not active

QSRI

BTS qSearchP With this parameter you define the threshold for

GPRS capable dual mode mobiles to search for

and to measure UTRAN neighbour cells

introduced in 3G Cell Reselection list when a

running average of the received downlink signal

level (RLA_C) of the serving cell is below (0-7)

or above (8-15) the threshold. This parameter is

broadcast on BCCH and used if GPRS cell re-

selection parameters for one or more cells are

sent to the MS in a Packet Cell Change Order

or Packet Measurement Order message

GPRS MS use this if IS-NCCR is active

QSRP

Range:

-98 dBm (0),

-94 dBm (1),

-90 dBm (2),

-86 dBm (3),

-82 dBm (4),

-78 dBm (RLA_C below) (5),


Infinity (measure always) (7),

-78 (RLA_C above) (8),


-70 (10),

-66 (11),

-62 (12),

-58 (13),

-54 (14),

Infinity (do not measure) (15)

Default = 15


WCDMA Measurement Triggering Dedicated mode parameter

Range:

-98 dBm (0),

-94 dBm (1),

-90 dBm (2),

-86 dBm (3),

-82 dBm (4),



Infinity (measure always) (7),



-70 (10),

-66 (11),

-62 (12),

-58 (13),

-54 (14),

Infinity (do not measure) (15)

Default = 15

MO

Class

Abbreviated

Name

Description BSC -

MML

Name

HOC qSearchC Threshold for multi-RAT MSs in dedicated state to

measure WCDMA RAN neighbour cells introduced

in 3G Cell Reselection list when the measured

downlink signal level (RLA_C) of the serving cell is

below (0-7) or above (8-15) the threshold.

Value 7 = measure always neighbour

WCDMARAN cell(s).

Value 15 = do not measure any of the neighbour

WCDMA RAN cells.

QSRC


Bookkeeping & Averaging Overview

measurement result averaging parameters averaged result

ECNO_NCELL(n) adjacent WCDMA RAN cell

averaging window size

AV_ECNO_NCELL(n)

number of WCDMA RAN zero

results

all adjacent WCDMA RAN cells

averaged

MS reports Ec/No of WCDMA cells as part of its measurement report every SACCH frame

Bookkeeping of measurements

Up to 32 WCDMA cells per GSM cell

Up to 32 measurement samples for each of the WCDMA neighbour cell

Averaging of measurements:


Bookkeeping & Averaging Parameters

MO

Class

Abbreviated

Name


value

BSC - MML

Name

HOC allUtranAdjAver N = the three best

RAN cells

Y = all adjacent

WCDMA RAN cells

Defines whether the signal measurement

results will be averaged for all adjacent

WCDMA RAN cells, or only for the three

best adjacent WCDMA RAN cells.

N (three

best)

UAAC

HOC noOfZeroResUt

ran

0...32, step 1 Defines the number of zero results that can

be omitted when the measurement results

of the adjacent WCDMA RAN cells are

averaged

5 UNOZ

HOC utranAveraging

Number

1...32, step 1

(SACCH periods)

Defines the window size for averaging the

signal quality, signal level and distance

measurement results that are adjacent

WCDMA RAN cell related

6 UAWS

MO

Class

Abbreviated

Name


value

BSC - MML

Name

HOC fddMultiratRep 0...3, step 1 Defines the number of the best valid

WCDMA RAN cells to be reported by a

dual mode mobile in the list of the

strongest cells or in the measurement

report.

2 FDMR


Cell Reselection GSM WCDMA


MS has to camp on a cell to get service from radio network A cell re-selection procedure ensures that the MS is camped on a cell

from which it can reliably decode downlink data and with which it has a high probability of communications on uplink

Cell reselection procedure is used in Idle mode Packet idle mode Packet transfer mode

Dual-mode mobile can perform cell re-selection from GERAN to UTRAN FDD cell

GSM coverage area ends (default 2G camping) UMTS coverage area starts (default 3G camping) Better UTRAN FDD cell available according the cell re-selection

parameters

Cell Re-Selection to WCDMA Overview


RLA_C means running average signal level which could be compared to received signal code power RSCP

Cell Re-Selection to WCDMA Procedure

Qsearch_I F(Qsearch_I )

0 -98

1 -94

2 -90

3 -86

4 -82

5 -78

6 -74

7 (always)

8 -78

9 -74

10 -70

11 -66

12 -62

13 -58

14 -54

15 (never).

UE starts WCDMA measurements when the running average signal level

(RLA_C) is below or above the threshold Qsearch_I

UE check if the RSCP of some neighbour WCDMA cell has exceeded

the RLA_C of the serving GSM cell and the neighbour GSM cells with the

parameter fdd and fdd cell reselct offset for a period of 5 sec

CPICH RSCP > RLA_C + FDD_Qoffset

UE checks that the WCDMA cells Ec/No has exceeded the minimum fdd threshold for a

period of 5 sec

CPICH Ec/No >= FDD_Qmin FDD_Qmin_Offset

UE checks that the WCDMA cells RSCP has exceeded the FDD RSCP

threshold for a period of 5 sec

CPICH RSCP >= FDD_RSCP_threshold

UE makes a cell reselection from the GSM to WCDMA cell

Start WCDMA measurements when a certain RxLevel is achieved in the

serving GSM cell

Compare RSCP of the WCDMA neighbour to the RxLevel of the

serving and neighbour GSM cells

WCDMA neighbour cells Ec/No must fullfil min requirement. Ec/No is a

good estimate of DL quality

WCDMA neighbour cells RSCP must fullfil min requirement. RSCP is a

good estimate of UL quality


Cell Re-Selection to WCDMA Parameters

MO

Class

Abbreviated

Name

Range And

Step

Description Default

value

BSC -

MML

Name

BTS fddQMin -20 dB to -6 dB

in 2 dB steps

Defines a minimum Ec/Io threshold which must be

exceeded before a non-GPRS capable dual mode

mobile is allowed to make a reselection from the

serving GSM cell to an adjacent WCDMA RAN cell

-12 dB

(7)

FDM

BTS fddQMinOffset 0...14 dB, step

2 dB

This parameter applies a negative offset to the

minimum Ec/No threshold for cell reselection from

the serving GSM cell to an adjacent UTRAN FDD

cell for dual-mode mobiles (R5 onwards)

0 dB FDMO

BTS fddQOffset -32...28 dB,

step 4 dB

Defines a UTRAN cell reselection offset for non-

GPRS capable dual mode mobiles which are in the

idle state

The mobiles add the offset to the running average (RLA_C) of the received signal level of the serving

GSM cell and non-serving GSM cells. After that the

mobiles compare the measured RSCP values of

UTRAN cells with signal levels of the GSM cells

-32 dB

(infinity)

FDD


t

Serving GSM Cell

Neighbour WCDMA Cell

Ec/No RSCP/ RLA_C

5 sec.

Cell re-selection to WCDMA

FDD_Qmin=0 (-20 dB)

FDD_Qoffset =6 (-8 dB)

Qsearch_I=0 (-98 dBm)

RLA_C

Measurements starts (serving cell)

Minimum Quality Requirement for WCDMA

Ec/N0

RSCP

Cell Re-selection Example - weaker WCDMA cell


2G

3G good Ec/No, low RSCP CPICH RSCP criterion in cell reselection will decrease the possibility for ping-pong between the systems

Ec/No as only criterion

2G

3G good Ec/No, low RSCP

RSCP as additional criterion

Received signal code power (RSCP) can be used as an additional 2G to 3G cell re-selection criterion

in idle mode to prevent ping-pong effect in 2G-3G cell reselection

CPICH is a common downlink pilot channel in 3G Can be used with all 3GPP Rel.5 and later terminals (RSCP criterion is an optional feature for

Rel.99 and Rel.4 terminals)

RSCP gives a better estimate of the 3G uplink performance than the earlier used reselection criterion

CPICH Ec/No alone

Without the use of RSCP criterion, the terminal could select a 3G cell with too weak signal and fluctuating Ec/No which could cause a return back to 2G network (ping-pong effect)

Note: Ec/No gives a good estimate of 3G downlink quality RSCP value measured by the terminal needs to exceed a certain threshold level managed by BSC,

before the measured 3G cell is taken as a target in the reselection process

GSM to WCDMA Advanced Cell Reselection Overview


Dual-mode mobile has two measurement quantities for neighbor UTRAN FDD cells

CPICH RSCP (Received Signal Code Power) Gives information about the coupling loss between BTS and MS

MS output power is mainly determined by the coupling loss => Uplink coverage is limited by MS maximum output power

Uplink quality is strongly dependent on CPICH RSCP

CPICH Ec/No (Ratio of energy per modulating bit to the noise spectral density) Gives composite measure of coupling loss (between BTS and MS) and

interference (neighbor cells, serving cell)

CPICH Ec/No provides a good estimate of downlink quality

GSM to WCDMA Advanced Cell Reselection Basics


The older dual-mode mobiles (before Rel 5.) do not take account the minimum CPICH RSCP level in their cell re-selection algorithm from GERAN to UTRAN cell

=> Cell re-selection can fail to UTRAN FDD cell because: CPICH RSCP is smaller than Qrxlevmin

Uplink connection does not success

Before Rel. 5

ping-pong possible

2G

3G

2G

3G

E.g. mobile selects WCDMA based on Good Ec/No

RSCP too low => sync fails. Reselect GSM

CPICH RSCP based criterion for 2G to 3G cell reselection Problem


Newer dual-mode mobiles (optional Rel99/4, mandatory Rel5 onwards) take account the minimum CPICH RSCP level in their cell re-selection algorithm from GERAN to UTRAN cell

2G

3G

Rel 5.

CPICH RSCP based criterion for 2G to 3G cell reselection Solution

X

WCDMA selected only

with minimum RSCP

- no ping-pong


Existing parameters:

FDD_Qoffset -> fddQOffset (FDD Cell Reselect Offset) (SEG) FDD_Qmin -> fddQMin (Minimum FDD Threshold) (SEG)

New parameters in S13:

FDD_RSCPmin -> fddRscpMin (Minimum RSCP Threshold) (SEG) FDD_Qmin_Offset -> fddQMinOffset (Minimum Fdd Threshold Offset) (SEG)

CPICH RSCP based criterion for 2G to 3G cell reselection Parameters


CPICH RSCP based criterion for 2G to 3G cell reselection Parameters

MO

Class

Abbreviated

Name

Range

And

Step

Description Default

value

BSC - MML

Name

BTS fddQMinOffse

t

0...14 dB,

step 2 dB

Applies a negative offset to the minimum Ec/No threshold

for cell reselection from the serving GSM cell to an

adjacent UTRAN FDD cell for dual-mode mobiles (R5

onwards).

Makes sufficient quality UMTS coverage look larger for

dual-mode mobiles that take account the minimum CPICH

RSCP level in the cell re-selection algorithm

0 dB FDMO

BTS fddRscpMin -114...-84

dBm,

step 2

dBm

Defines the minimum RSCP threshold for cell reselection

from the serving GSM cell to an adjacent UTRAN FDD cell

for dual-mode mobiles (R5 onwards).

-102

dBm

FDR


GSM to WCDMA Advanced Cell Reselection Idle Mode

If the broadcast neighbour cell list from the BSC to the mobile contains information on WCDMA RAN cells, the mobile updates the value RSSI for the serving cell and each of the at least six strongest non-serving GSM cells at least every five seconds. The mobile reselects a suitable WCDMA RAN cell according to the following three criteria:

1. its measured RSCP value exceeds the value of RSSI for the serving cell and all of the suitable (see 3GPP TS 03.22) non-serving GSM cells by the value FDD_Qoffset,

If its measured RSCP value exceeds the value of RSSI for the serving cell and all of the suitable non-serving GSM cells by the value QSRI (QSRP) for period of five seconds. This means that with positive offset value the WCDMA cell should be better than GSM cell and vica versa.

2. its measured Ec/No value is equal or greater than the value FDD_Qmin, and

For FDD the mobile selects the WCDMA cells, whose measured Ec/No value is equal or greater than the value FDDQmin.

3. its measured RSCP value is equal to or greater than FDD_RSCP_threshold (In R99/R4 if supported by the MS).


GSM to WCDMA Advanced Cell Reselection Idle Mode Criteria 3 was introduced in R99/R4/R5 specifications on 2004-08 and the exact definition varies between R99/R4 and R5 (see 3GPP TS 05.08 version 8.21.0 Release 1999, 3GPP TS 45.008 version 4.15.0 Release 4 and 3GPP TS 45.008 version 5.19.0 Release 5 or later specs). CPICH RSCP Based Criterion for 2G to 3G Cell Reselection is a BSS S13 feature.

FDD_RSCP_threshold is defined in R5 as: FDD_RSCPmin min((P_MAX 21 dBm), 3 dB), if FDD_RSCPmin is broadcast on

the serving cell,

Qrxlevmin + Pcompensation + 10 dB, if these parameters are available Pcompensation is max(UE_TXPWR_MAX_RACH P_MAX, 0) (dB),

The default value of FDD_RSCPmin (-102 dBm).

Criteria 2 was changed in R5 specifications to be:

2. its measured Ec/No value is equal or greater than the value FDD_Qmin - FDD_Qmin_Offset

The broadcasting of FDD_Qmin_Offset is a BSS13 feature, default is 0 dB.

Thus, the final GSM to WCDMA re-selection criteria R5 specification is

ThresholdRSCPFDDRSCP

ffsetFDD_Qmin_oFddQminIoEc

FddQoffsetGSMRSSIRSCP

ANDcriterianreselectioCellWCDMAGSM

__

/

_

:


GSM to WCDMA Advanced Cell Reselection Packet Mode

New parameters FDD_Qmin_Offset and FDD_RSCPmin are introduced for re-selection algorithm.

The FDD cell re-selection parameters FDD_Qmin_Offset and FDD_RSCPmin shall be broadcasted on BCCH within the SI2ter and SI2quater messages. Dual-mode mobiles in idle mode read these messages. If PBCCH does not exist on the serving cell then also dual-mode mobiles in packet idle mode read these messages from BCCH.

Dual-mode mobile (R5 and R6) in packet idle mode or packet transfer mode selects FDD cell as target cell during cell re-selection when all the following criterias are met for a period of 5 seconds

1. FDD cells measured RSCP value exceeds the value of RLA_P for the serving cell and the all of the suitable non-serving GSM cells by the value FDD_GPRS_Qoffset

2. FDD cells measured Ec/No value is equal or creater than the value FDD_Qmin FDD_Qmin_Offset and

3. FDD cells measured RSCP value is equal or greater than the value FDD_RSCP_threshold


GSM to WCDMA Advanced Cell Reselection Packet Mode

FDD_GPRS_Qoffset corresponds the SEG specific BTS radio network object parameter FDD cell reselect offset (FDD) in Nokia BSC. If PBCCH exists in the cell then the FDD_GPRS_Qoffset corrsponds the SEG specific BTS radio network object parameter GPRS fdd cell reselect offset (GFDD).

FDD_Qmin corresponds the SEG specific BTS radio network object parameter minimum fdd threshold (FDM) in Nokia BSC. If PBCCH exists in the cell then the FDD_Qmin corresponds the SEG specific BTS radio network object parameter GPRS minimum fdd threshold (GFDM).

FDD_RSCP_threshold equals FDD_RSCPmin min((P_MAX 21 dBm), 3dB) if FDD_RSCPmin is broadcasted on the serving cell else mobile calculates value for it or uses default value.



To remove unnecessary signalling and to reduce the delay in service access, mobile stations can be commanded to directly camp to a 3G cell after call release in 2G

Supported by 3GPP Rel.6 and later terminals Direct camping to 3G can avoid LAU/RAU signaling process which typically takes

25 seconds

Direct camping information is indicated by BSC to all dual-mode terminals when they report at least one 3G neighbor cell

The reported 3G cell is used as a target cell in Channel Release message (Information Element: Cell Selection Indication after release of TCH and SDCCH)

If several 3G neighbor cells are reported by the terminal, then the best one is used as a target for idle mode camping

without: 3G idle 3G 2G 2G LAU/RAU

2G-camping after call terminates

3G LAU/RAU

Default 3G camping

3G idle

3G idle 3G 2G 3G idle with:

Handover to 2G

Unnecessary RAU/LAUs can be avoided RAU = routing area update

LAU = location area update

Voice call setup in 3G

Channel release: directly camp on 3G


Inter-System NCCR (IS-NCCR) Introduction

Inter-System Network-Controlled Cell Re-selection (IS-NCCR) allows the network the possibility to order a cell re-selection from a GSM cell to a WCDMA RAN cell (instead of the autonomous selection done by the MS itself).

With this feature, the network decides when the MS changes cell and what the target cell is.

IS-NCCR introduces the possibility for the network to control timing and target cell selection in cell re-selection. There are the following cell re-selection criteria:

Service-based IS-NCCR: allows the operator to direct MSs to a preferred radio system according to the services they use. It selects 3G network according to SGSN Service UTRAN CCO BSSGP (Cell Change Order BSSGP signaling) procedure even if the serving cell signal level is good.

Coverage-based IS-NCCR: enables the operator to define whether 3G network is selected as soon as WCDMA FDD cell coverage is available or only when GSM coverage ends

In target WCDMA FDD cell prioritization, the PCU ranks the target cell candidates based on the reported Ec/No value.


Inter-System NCCR (IS-NCCR) Description

Inter-system cell re-selection also depends on the Service UTRAN CCO value received from the SGSN

The cell re-selection can be carried out in the following cases:

WCDMA

FDD NCCR

enabled

WCDMA

FDD NCCR

preferred

Service UTRAN CCO

Information Element

(IE) indication for

NCCR to UTRAN

(received from

SGSN)

Additional condition

Service-based IS-NCCR On Off Should be performed

WCDMA-coverage-

based IS-NCCR

On On Should not be

performed

GSM-coverage-based

IS-NCCR

On Off Should not be

performed

The serving and

neighbour GSM cells do

not fulfil the minimum

Rxlev requirements


Inter-System NCCR (IS-NCCR) Coverage criteria overivew

WCDMA FDD NCCR Preferred

Select suitable WCDMA cell

Suitable GSM cell available?

Has SGSN denied IS NCCR

by Service UTRAN COO IE?

IS-NCRR to WCDMA

On

Off

No

Yes No IS-NCCR

No

Yes


Inter-System NCCR (IS-NCCR) Service criteria overivew

WCDMA FDD NCCR Preferred

Select suitable WCDMA cell

Suitable GSM cell available?

Check Service UTRAN COO IE

value

Off

Shall not

Shall not No IS-NCCR

Should be done

On

Coverage criteria

IS-NCRR to WCDMA

No

Yes


Inter-System NCCR (IS-NCCR) Priority order of cell reselection criteria (Coverage & Service)

AV_3G_MES_QUAN(n) is the average of 3G measurement quantity

CellReselQual3GRAThr is determined by adjacent WCDMA RAN cell parameter ISNCCR FDD quality threshold (FQT)

AV_RXLEV_SERV and AV_RXLEV_NCELL(n) are measured DL Rx Level on the BCCH of serving and neighbour cell

Pa = GPRS_MS_TXPWR_MAX_CCH(n) P , where P = max GMSK output power capability of the MS

IS-NCCR to WCDMA FDD cell is triggered when

serving and neighbour GSM cells do not fulfill the

minimum RXLEV requirements

AV_RXLEV_SERV > gprsRxLevMinCell + MAX(0, Pa), or

AV_RXLEV_NCELL(n) > gprsRxLevMinCell(n) + Max(0, Pa)

and

any of the WCDMA FDD neighbour cells fulfill the equation

AV_3g_MES_QUAN(n) > CellReselQual3GRATThr(n)

IS-NCCR to WCDMA FDD cell is triggered when any of

the WCDMA FDD neighbour cells fulfills the equation

AV_3G_MES_QUAN(n) > CellReselQual3GRATThr(n)

IS-NCCR not started

Service UTRAN CCO WCDMA FDD NCCR Preferred

value"...should be done..."

value"...shall not be done..."

value "...should not be done..."

IE not provided by SGSN

On

Off


Inter-System NCCR (IS-NCCR) Parameters

MO

Class

Abbreviated

Name

Range And

Step

Description Default

value

BSC - MML

Name

ADJW isnccrFddQualit

yThr

-24...0.5 dB,

step 0.5 dB

With this parameter you define the minimum

signal quality level of an adjacent WCDMA RAN

cell for an inter-system network-controlled cell re-

selection (ISNCCR).

Value 0.5 dB = the BSC is never allowed to initiate

an ISNCCR attempt from the serving cell towards

the WCDMA RAN cell

-15 dB FQT

BSC wcdmaFddNccr

Enabled

N, Y Switches on or off the ISNCCR to WCDMA FDD

cells

N WFNE

BSC wcdmaFddNccr

Preferred

N, Y Y = Coverage reason ISNCCR is triggered as

soon as an appropriate WCDMA cell is available

(Service UTRAN CCO IE value sent by SGSN is

ignored)

N = ISNCCR is triggered only in case there is not

an appropriate GSM/EDGE cell available and an

appropriate WCDMA cell is available. MML

default: Y

Y WFNP


Three features are introduced in RG20 for improving BSS11.5 NACC functionality by means of:

Inter-BSC NACC (IB-NACC)

Inter-System NACC (IS-NACC)

Inter-System NACC from LTE (LTE-NACC)

With the help of IB-NACC feature network assisted cell changes are possible between different BSCs

Similarly, in case of IS-NACC inter-system NACC from UTRAN to GSM could take place and in case of LTE-NACC IS-NACC from LTE to GSM is possible (assuming that the network which the NACC is originated from supports this functionality)

Following information are transferred between BSCs and from BSC to RNC or eNB:

SI1, SI3, SI13

System implementation

RG20 (BSS) NACC Improvements Feature details


New parameters

ibNaccEnabled IBNACC Enabled

Object: BSC

Range: 0, 1

Default: 0

HIDDEN Parameter

Define the state of the IBNACC feature

0 disabled

1 enabled

Set by the system to enabled only if license for NACC is activated, NACC is enabled and license for IBNACC is activated

ibNaccState IBNACC State

Object: ADCE

Range: 0, 1

Default: 1

MML commands: EAO

Parameter indicates whether IBNACC feature in the adjacent segment (in adjacent BSC) is enabled or not. Modified only by the system.

If the parameter is set to 1 (disabled), polling is started (according to setting of PRFILE parameter IBNACC_POLLING_TIME) by sending RAN-INFORMATION-REQUEST/Multiple Report to serving BSC.

If IB-NACC is supported in the adjacent external cell, appropriate information is sent in CCN_SUPPORTED information in SI2quater.

0 supported

1 not supported

Parameter is meaningless in case of own BSC segments.

RG20 (BSS) NACC Improvements Parameters


New PRFILE parameter

IBNACC_POLLING_TIME IB-NACC Polling Time

PRFILE

Range: 1, , 15min

Default: 5

Defines the interval which is used between two consecutive RIM request messages when no NACC data exists for BSC external 2G adjacent cell in PCU2.

Timer is used for Inter-BSC NACC feature, mainly for error handling in BSC-BSC procedures.

RG20 (BSS) NACC Improvements Parameters

Modified parameters

No changes in the existing parameters


Handover GSM WCDMA


GSM

GSM

Inter System Handover Overview

GSM

GSM high loaded

WCDMA low loaded

GSM GSM

WCDMA WCDMA

Load reason Handover for speech

WCDMA GSM

Coverage, Load and service reason Handover

Coverage Load and service reason Handover

WCDMA can be used to relieve GSM overload

GSM can be used to extend

WCDMA coverage area

Mobile moving


Inter-System Handover Procedure to WCDMA Prerequisites

The target cell candidates (WBTSs) are defined as neighbour WCDMA RAN cells for the serving GSM cell in the BSC.

The UEs (which are in the dedicated state) are allowed to measure the neighbour WCDMA RAN cells of the serving GSM cell. The starting point for measurements is defined with the parameter QSearchC (qSearcC parameter is similar to the previously mentioned idle mode parameter QSRI)

The MS has sent the neighbour WCDMA RAN cell measurements to the BSC. This is controlled by FDMR (number of measured FDD cells) parameter

Early classmark sending is allowed for mobiles in the serving GSM cell. This is set by parameter early sending indication (ESI).

The mobile has sent the UTRAN CLASSMARK CHANGE message to the BSC.

A dual mode GSM/WCDMA mobile sends a UTRAN CLASSMARK CHANGE message to the BSC if the early classmark sending is allowed in the serving GSM cell. The content of the message is required by an RNC, which controls the target WCDMA RAN cell of the inter-system handover attempt.

The connection-specific penalty timer for inter-system handover attempts has been expired.


BSC checking the set handover triggering thresholds

Inter-RAT measurements starts in case the RXLEV of the serving cell is above or

below the given threshold Qsearch_C, (threshold for Multi-RAT MS)

Handover decision is done in case of

load of the serving cell > load_Threshold

and CPICH Ec/No (WCDMA neighbour) > Min Ec/No

Threshold. Load of the serving GSM cell is ignored if

the handover is triggerred due to GSM coverage

reason or service priority

BSC selects the target UTRAN cell based on measurement results

Handover request is send to MSC

Min traffic load threshold = 60% Min CPICH Ec/Io level = 18 (-15dB)

Inter-System Handover Procedure to WCDMA Load based procedure

Load checking is similar compared to the BSC initiated Traffic Reason Handover . The BSC

initiates only as many inter-system handovers as the number of ongoing calls in the serving GSM cell is over the traffic load threshold. That is, the

serving GSM cell is not emptied into the WCDMA RAN.

Traffic load

of serving

GSM cell

Avg

Ec/No of

WCDMA

cell

Traffic

load

Signal

Quality

ISHO

possible?

45% 18 Too low Too low No

45% 19 Too low Ok No

65% 19 Ok Ok Yes

Example


Inter-System Handover Procedure to WCDMA Load based parameters

MO

Class

Abbreviated

Name

Range And

Step

Description Default

value

BSC -

MML

Name

ADJW minEcnoThresh

old

-24...0.5 dB,

step 0.5 dB

Defines the minimum CPICH Ec/Io threshold level of

an adjacent WCDMA RAN cell which must be

exceeded for an inter-system handover attempt.

NOTE: The value 0.5 dB = BSC is never allowed to

initiate a handover attempt from the serving GSM

cell towards the WCDMA RAN cell

-15 dB MET

HOC qSearchC 0...15, step 1 Threshold for multi-RAT MSs in dedicated state to

measure WCDMA RAN neighbour cells introduced

in 3G Cell Reselection list when the measured

downlink signal level (RLA_C) of the serving cell is

below (0-7) or above (8-15) the threshold.

Value 7 = measure always neighbour WCDMARAN

cell(s).

Value 15 = do not measure any of the neighbour

WCDMA RAN cells.

15 QSRC

HOC utranHoThScTp

dc

0...100 %, step

1 %

Defines the minimum traffic load that must be

exceeded on the serving GSM cell before the

handover algorithm is allowed to initiate a handover

for a speech call from the serving GSM cell to a

WCDMA RAN cell.

80 % LTSC


ISHO Penalties and Timers Connection specific penalty timers

Connection-specific penalty timers

Min int between HO requests

Min int between unsuccessful HO requests

After unsuccessful GSM WCDMA attempt: Min int between unsuccessful ISHO att (UMIU)

After successful WCDMA GSM handover: BSC wont allow ISHO back to WCDMA for the same connection for 30 sec

The same timers used in GSM handover control

MO

Class

Abbreviated

Name

Range And

Step

Description Default

value

BSC -

MML

Name

HOC minIntUnsuccIs

Ho

0...255 s,

step 1 s

The minimum time interval between inter-system

handover attempts related to the same connection

and the same non-GSM cell when a handover

attempt from the serving GSM cell to a non-GSM

cell has been unsuccessful.

3 s UMIU


ISHO Penalties and Timers Cell based penalty timers

Cell-based penalty timers after unsuccessful HO from GSM WCDMA

Repeated unsuccessful ISHO att to WCDMA cell indicate that the WCDMA cell is loaded

GSM GSM GSM

3G 3G

ISHO att from other cells during time N are allowed

If X % of ISHO fail during a time period T (window) prevent ISHO attempts for N amount of time

Triggering ratio for WCDMA RAN cell penalty (X)

Penalty trigger measurement period (T)

WCDMA cell RAN penalty time (N)


ISHO Penalties and Timers Cell based penalty timers (parameters)

MO

Class

Abbreviate

d Name


value

BSC -

MML

Name

BSC triggerMeas

Period

N, 2...254 seconds,

step 2 seconds

Length of the period during which the latest ISHO

counters are used, if the WCDMA RAN Service

Area and neighbour WCDMA RAN cell penalty

triggering are used

N= WCDMA RAN service area and neighbour

WCDMA RAN cell penalty triggering is disabled

128

seconds

PTMP

HOC failMoveThr

eshold

0...100 %, step 1 % The percentage of unsuccessful outgoing ISHO

attempts towards a certain adjacent WCDMA cell

that must be exceeded during a certain time (set

by parameter PTMP) for the penalty timer (WCP)

to be applied

50% TRW

HOC wcdmaRan

CellPenalty

0...255, step 1 The duration of a handover penalty timer that has

been triggered on a serving GSM cell for an

adjacent WCDMA RAN cell

127 WCP


service

area 1

service

area 2

service

area 3

cell 1

cell 2

cell 3

cell 4

cell 5

cell 6

cell 7

cell 8

cell 1

cell 2

cell 3

cell 4

cell 5

cell 6

cell 7

cell 8

WCDMA RAN BSC

After a certain number HO attempts from

the WCDMA RAN service area 1 are

successful within a predefined time period,

the BSC has to put the source WCDMA

RAN service area 1 to the penalty bench.

That is, during the predefined penalty time,

the BSC is not allowed to initiate handover

attempts back to the source WCDMA RAN

service area 1.

ISHO Penalties and Timers Service area based penalty timers

Applied after successful HO WCDMA GSM


service

area 1

service

area 2

service

area 3

cell 1

cell 2

cell 3

cell 4

cell 5

cell 6

cell 7

cell 8

WCDMA RAN

During the penalty

time HOs from the

GSM to the WCDMA

RAN

service area 1 are not

allowed

BSC

cell 1

cell 2

cell 3

cell 4

cell 5

cell 6

cell 7

cell 8

ISHO Penalties and Timers Service area based penalty timers

Applied after successful HO WCDMA GSM

Service Area 1 is considered loaded prevent ISHO back to

that area


ISHO Penalties and Timers Service area based penalty timers (parameters)

MO

Class

Abbreviated

Name


value

BSC -

MML

Name

ADJW sac 0...65535, step 1 With this parameter you define the service area

the adjacent UTRAN cell belongs to.

SAC

BSC incomeRateT

hreshold

0...255, step 1 Defines the triggering level for a Service Area

penalty. If the number of incoming Inter-System

Handovers which occur from a certain Service

Area exceed the penalty triggering level during a

measurement period, the Service Area-specific

penalty timer is triggered

127 TTSAP

BSC triggerMeasP

eriod

2...254 seconds,

step 2 seconds

Length of the period during which the latest ISHO counters are used, if the WCDMA RAN Service Area and neighbour WCDMA RAN cell penalty triggering are used

N= WCDMA RAN service area and neighbour WCDMA RAN cell penalty triggering is disabled

128

seconds

PTMP

BSC wcdmaRanS

aiPenalty

0...255 sec, step

1 sec

Duration of the handover penalty timer which has

been triggered for a Service Area. While the

Service Area penalty timer is on, the BSC is not

allowed to initiate an Inter-System Handover

attempt towards WCDMA RAN cells that belong to

the Service Area.

127 sec SAPT


SDCCH channel

1. Direct Access or inter-system direct access to WCDMA RAN 2. Interference (uplink or downlink) 3. Intra-segment inter-band due to downlink level (from higher to lower frequency band) 4. Uplink quality 5. Downlink quality 6. Uplink level 7. Downlink level 8. MS-BS distance (maximum or minimum) 9. Turn-around-corner MS 10. Rapid field drop 11. Fast/slow-moving MS 12. Power budget

TCH channel

1. Interference (uplink or downlink) 2. Intra-segment inter-band due to downlink level (from higher to lower frequency band) 3. Uplink quality 4. Downlink quality 5. AMR unpacking (uplink level and also uplink unpacking quality triggers) 6. Uplink level 7. AMR unpacking (downlink level and also downlink unpacking quality triggers) 8. Downlink level 9. Inter-System Handover to WCDMA RAN (Only the first 9 handovers are listed here)

Interaction between ISHO and Intra-GSM Handovers

Handover Priority Order


Interaction between ISHO and Intra-GSM Handovers

The use of priorities means that the inter-system handover procedure will not be triggered in certain scenarios when for example quality, DL RX Level or interference levels have reached the thresholds.

As an example, when cell load exceeds the load threshold, if DL HO RX Level threshold is set to 95 dBm, ISHO will not occur for MSs that are beyond the -95dBm on DL Rx Level (BSC will try to do handover to another GSM cell instead of to 3G)

RXLEV=-95 dBm

4 1

2

5 6

3

Terminals 1, 2 and 3 may be moved to 3G

Terminals 4,5 and 6 may only be moved to another GSM cell (DL RXLEV handover)


Inter-System Direct Access Overview

Enable the BSC to hand a mobile directly from the SDCCH to the WCDMA Triggering based on GSM load, similar feature as GSM internal direct access

(DADL/B)

2G/MSC

BSC

(1) Mobile camps to GSM, and requests a service

RNC

(2) BSC receives service priority from MSC with

value should

(3) BSC makes a Direct Access to WCDMA RAN

3G/MSC

(4) Mobile starts the service in WCDMA


Inter-System Direct Access Procedure

Mobile camps to GSM cell. Requirements has to be fulfilled: Inter-system handover is enabled and Direct Access is allowed

The BSC must have received an indication from the UE about its WCDMA RAN capability in the CLASSMARK CHANGE message. The UE has to be FDD capable. The message must already have been received on the SDCCH.

The BSC has received the service priority with the value 'should' from the MSC.

Note that inter-system direct access begins only if the service priority is set to should.

The UE must have already received information about the adjacent WCDMA RAN cells from the BSC on the SDCCH.

The MSC must support the sending of the Service Handover information element in the ASSIGNMENT REQUEST message. The value of the service priority has to be set to SHOULD. For more information on service priority, see Support of service priorities in A-interface.

The BSC has to have received measurement reports of the WCDMA RAN adjacent cell(s) already on the SDCCH.

The Ec/No of the target WCDMA RAN cell has to be over the Inter-System Direct Access threshold direct access EC/IO threshold.


Inter-System Direct Access Parameters

MO

Class

Abbreviated

Name

Range And

Step

Description Default

value

BSC -

MML

Name

ADJW intSystemDaE

cioThr

-24...0.5 dB,

step 0.5 dB

Defines the minimum CPICH Ec/Io level of an

adjacent WCDMA RAN cell in decibels, when a

direct access to the adjacent WCDMA RAN cell is

allowed.

Value 0.5 = the BSC is not allowed to initiate a direct

access from the serving GSM cell to the WCDMA

RAN cell because a CPICH Ec/Io level measured by

mobiles can be maximum 0 dB.

-11.5 dB DET

HOC interSystemDa false (0),

true (1)

This enables or disables the Inter-System Direct

Access to the WCDMA RAN.

Yes = the Inter-System Direct Access to the WCDMA

RAN is tried first

false (0) IDE


2G

3G good Ec/No, low RSCP CPICH RSCP criterion will improve the ISHO or IS-NCCR success rate


2G



Received signal code power (RSCP) can be used as an additional 2G to 3G cell inter-system handover

or IS-NCCR criterion in dedicated mode to improve 2G to 3G handover/cell reselection success rate

CPICH is a common downlink pilot channel in 3G Can be used with 3GPP Rel.5 and later terminals (RSCP criterion is an optional feature for


RSCP gives a better estimate of the 3G uplink performance than the earlier used reselection criterion

CPICH Ec/No alone

Without the use of RSCP criterion, the terminal could directed to a 3G cell with too weak signal and fluctuating Ec/No which could cause a return back to 2G network


before the measured 3G cell is added in the measurement report sent back to BSC

WCDMA Neighbour Cell Reporting Enhancement Overview


Inter System Handover (ISHO) procedure is used for dual-mode mobiles in dedicated mode to offer seamless service between the radio access technologies

Inter System Network Controlled Cell Reselection (IS-NCCR) procedure is used for dual-mode mobiles in packet transfer mode to offer seamless service between the radio access technologies

BSC can start ISHO (or IS-NCCR) procedure from GERAN to UTRAN FDD cell when

GSM coverage area ends UMTS coverage area starts Better or less loaded UTRAN FDD cell is available according the

handover control parameters

BSC needs measurement results concerning the neighbor UTRAN FDD cells to able to make decision to start ISHO or IS-NCCR



BSC makes decisions for ISHO and IS-NCCR based on measurement reports it receives from the mobile

Because CPICH Ec/No is the reported measurement quantity then only downlink quality is taken account in the decision

BSC can trigger ISHO or IS-NCCR to UTRAN FDD cell that has good downlink quality but poor uplink quality => ISHO or IS-NCCR fails

Before Rel. 5

ping-pong possible

2G

3G

2G

3G

E.g. mobile selects WCDMA based on Good Ec/No

RSCP too low => sync fails. Reselect GSM

WCDMA Neighbour Cell Reporting Enhancement Problem


WCDMA Neighbour Cell Reporting Enhancement Solution

Newer dual-mode mobiles (Rel 5. onwards) do not send measurement reports of UTRAN FDD cells whose CPICH RSCP is below the threshold defined by FDD_REPORTING_THRESHOLD_2 parameter

=> BSC does not trigger ISHOs or IS-NCCRs to these cells

2G

3G

Rel 5.

ISHO or IS-NCCR is not triggered to cells with too low CPICH RSCP

MO

Class

Abbreviate

d Name

Range And

Step

Description Default

value

BSC -

MML

Name

HOC fddRepThr2 -115...-53

dBm, step

1 dBm

Defines the reporting threshold for the adjacent UTRAN

FDD cell in the serving GSM cell. The non-reported

measugrement quantity CPICH RSCP has to be equal or

greater than the threshold value before the UTRAN FDD

cell is reported.

-105

dBm

FRT2

X


Coverage Based ISHO for Voice

Ongoing voice call is typically kept in GSM network as long as there is good enough

network coverage. Handovers are primarily done between GSM cells.

In case of poor 2G network coverage, the call is handed over to 3G network

Inter-system handover will be performed even though intra-system handover

criteria were prioritised over inter-system criterion

GSM GSM GSM GSM

3G 3G 3G 3G

GSM 3G GSM 3G

Load reason handover from GSM to 3G

Coverage reason handover from 3G to GSM

Coverage reason handover from GSM to 3G

Load threshold

Dual mode mobile

When higher priority intra GERAN handover criteria is exceed, but no target GSM cell can be found, the BSC can trigger inter-system handover even load of the source cell is below the load threshold


Coverage Based ISHO for Voice dedicated mode

When any intra GSM handover criteria before low signal strength criterion is met but does not lead in handover initiation, RCSPRB shall continue to evaluate the next, i.e. signal strength handover criterion.

When uplink or downlink signal strength meets the intra GSM handover criterion for low signal strength, but it does not result in handover initiation, RCSPRB shall evaluate a possibility to perform an inter-system handover from GSM cell to UTRAN cell.

Although serving GSM cell load might be checked in normal inter-system handover initiation, in this case it shall have no effect to an inter-system handover initiation. However, an inter-system handover shall not be initiated if the final service priority compiled of priorities received from the MSC and/or from the SGSN completely denies an inter-system handover.



Main Success Scenario:

RCSPRB receives radio link measurements from the BTS and from the UE.

One or several higher priority intra GSM handover criteria, including low signal strength criterion, are exceeded. RCSPRB does not start an intra GSM handover because of not good enough GSM adjacent cells available for the handover.

The inter-system handover criterion is evaluated and exceeded. UTRAN cell that the UE reported is good enough for starting the inter-system handover from GSM cell to UTRAN cell although serving GSM cell load is below load threshold for an inter-system handover.

The UE is successfully hand-overed from GSM cell to UTRAN cell.



New HO and PC algorithm allows ISHO in case some of higher priority triggers are met, but handover not possible due conflict with some other criteria. Priority of coverage based ISHO is updated to level 9 ( old ISHO was level 13 and not possible if higher level HO decision in process )GERAN to UTRAN handover is executed only if Service Handover IE ( of Assignment request or Handover Request) does not deny it ( 3GPP 48.008 Rel 6 clause 3.2.2.75)

New HO decision priority table: 1. Interference (uplink or downlink)

2. Intra-segment inter-band because of downlink level (from higher to lower frequency band)

3. Uplink quality

4. Downlink quality

5. AMR unpacking (uplink level or uplink unpacking quality triggers)

6. Uplink level

7. AMR unpacking (downlink level or downlink unpacking quality triggers)

8. Downlink level

9. Coverage based inter-system handover to WCDMA RAN

10. IMSI-based inter-system handover to WCDMA RAN

11. IMSI-based handover

12. DTM-based handover to WCDMA RAN

.

.


2G

3G good Ec/No, low RSCP CPICH RSCP criterion will improve the ISHO or IS-NCCR success rate


2G



Received signal code power (RSCP) can be used as an additional 2G to 3G cell inter-system handover

or IS-NCCR criterion in dedicated mode to improve 2G to 3G handover/cell reselection success rate

CPICH is a common downlink pilot channel in 3G Can be used with 3GPP Rel.5 and later terminals (RSCP criterion is an optional feature for


RCSP gives a better estimate of the 3G uplink performance than the earlier used reselection criterion

CPICH Ec/No alone

Without the use of RSCP criterion, the terminal could directed to a 3G cell with too weak signal and fluctuating Ec/No which could cause a return back to 2G network


before the measured 3G cell is added in the measurement report sent back to BSC

WCDMA Neighbour Cell Reporting Enhancement Introduction


WCDMA Neighbour Cell Reporting Enhancement New parameter

A new reporting parameter FDD_REPORTING_THRESHOLD_2 is introduced in Measurement Information and System Information Type 2quater messages on CS domain and in Packet Measurement Order, Packet Cell Change Order, PSI3quater and PSI5 messages on PS domain.

This new parameter sets threshold value for non-reported CPICH RSCP measurement quantity of neighbor UTRAN FDD cell. Dual-mode mobile that supports the FDD_REPORTING_THRESHOLD_2 parameter does not report neighbor UTRAN FDD cells that have CPICH RSCP value below the FDD_REPORTING_THRESHOLD_2 parameter.

This feature does not change structure of measurement reports and it does not have influence to ISHO / ISNCCR algorithms of BSC. BSC manages the new FDD_REPORTING_THRESHOLD_2 parameter and delivers it for dual mode mobiles.

Documents

05_RN20115EN20GLN0_ISHO