05 Mn1789eu12mn 0001 Gsm Umts Interworking

8/12/2019 05 Mn1789eu12mn 0001 Gsm Umts Interworking

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GSM-UMTS Interworking

MN1789EU12MN_0001 2007 Nokia Siemens Networks

1

Contents

1 Introduction 3

1.1 Cell reselection from GSM to UMTS 6

1.2 Database Parameters 8

2 Handover from GSM to UMTS 9

2.1 Basics 10

2.2 SBS implementation 12

2.3 GSM to UMTS Handover Types 14

2.4 Generation of target cell list 20

2.5 BSC Database parameters 24



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2007 Nokia Siemens Networks2


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3

1 Introduction


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Since release BR7.0 SBS equipment fully supports GSM -UMTS interworking. Underinterworking it is assumed the system capability to support intersystem (2G->3G) cellreselection as well as handover from GSM to UMTS for circuit switched voice and

data services.Therefore, these cell reselection and handover features are particularly important inthe early UMTS introduction phases where the UMTS system only covers relativelysmall areas. Operators equipped with both technologies (GSM and UMTS) can makethe best use of their UMTS islands. New UMTS operators, who have not installedGSM systems, will have to pay for GSM network usage and will therefore demand aGSM-UMTS inter-working to minimize their costs.

The network consisting of both technologies and supported by the same corenetwork is called multi-RAT (Radio Access Technologies) network while the MS/UEis dual mode terminal. Umair interface is used to establish and hold the connection

with a GSM BTS, whereas the Uu interface establishes and holds the connectionswith a UMTS base transceiver stations (Node B).


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Uu

RNC

(Target) UMTS Cell(Source) GSM Cell

NodeB

BSC

BTS

Um

2G-3G-MSC

(Visited)

(Circuit Switched) Voice & Data

Mobile (MS/UE)

IubAbis

Fig. 1 Multi-RAT Network


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1.1 Cell reselection from GSM to UMTS

The inter-system cell reselection from GSM to UMTS allows a MS to reselect to theUMTS system.

The cell reselection feature is important to guarantee a better quality connectionwhen the mobile detects a stronger signal from a neighbor cell, even if this cellbelongs to another Radio Access Technology (RAT).

If an FDD cell is suitable, the following two conditions must be fulfilled:

1. For a period of 5 seconds, the measured RSCP value must exceed the RLA ofthe serving GSM and of all non-serving GSM cells by the value FDD_Qoffset.

2. The measured Ec/No of the FDD cell must be greater or equal than the value

FDD_Qmin broadcast in the serving cell.

The principles of the cell reselection from GSM to UMTS are displayed in the figurebelow.


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5sec

Qsearch_I

start WCDMA

measurements

RLA of serving GSM cell

RSCP of WCDMA

neighbor cell

RLA of (non serving) GSM

neighbor cell

Cell Reselection

(only if CPICH Ec/No

is greater or equal

FDD_Qmin)

FDD_Qoffset

Time

Fig. 2 Principle of the GSM to UMTS cell reselection


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1.2 Database Parameters

Parameter Range (Default) Object Meaning

QSRHI UMDB98, UMDB94, UMDB90,UMDB86, UMDB82, UMDB78,UMDB74, ALWAYS, OMDB78,OMDB74, OMDB70, OMDB66,OMDB62, OMDB58, OMDB54,NEVER

Default = NEVER

BTS This attribute defines athreshold which enables thesearching for 3G cells withregard to cell reselection. Itindicates when themeasurements of 3G cellshave to be initiated.

FDDQMI MDB20, MDB19, MDB18,MDB17, MDB16, MDB15,MDB14, MDB13, NULL,

Default = NULL

BTS The FDDQMI thresholddefines a minimum CPICHEc/No for a WCDMA cell forcell re-selection.

FDDQO ALWAYS, MDB28, MDB24,MDB20, MDB16, MDB12,MDB08, MDB04, DB00, DB04,DB08, DB12, DB16, DB20,DB24, DB28

Default: DB00

BTS The FDDQO defines an offsetvalue, which has to be addedto the RLA of the serving andnon-serving GSM cells. Theresult is compared with theRSCP value of the WCDMA

cell.


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9

2 Handover from GSM to UMTS


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2.1 Basics

All handover specific evaluations are performed by the GSM base station system(and not by the UMTS radio network system). The BSS informs the mobiles aboutUMTS neighboring cells via appropriate system info messages. Multi-RAT capability(GSM, UMTS) of mobiles is indicated to the network, as the mobiles send theclassmark information to the BSS.

Within BR 6.0 the two following features were introduced:

Intersystem Cell Reselection between GSM/GPRS and UMTS

Handover (Circuit switched) from UMTS to GSM

Thus, HO from GSM to UMTS completes the interworking between GSM and UMTS

(FDD or TDD network).

The number of supported neighbor cells is 96 neighbor cells in total:

32 GSM neighbor cells

64 UMTS neighbor cells.

Calls established within the GSM system can be handed over to a UMTS system dueto one of the following reasons:

Emergency Handover (quality, signal strength, distance, forced)

Better cell

Sufficient UMTS coverage.

As for circuit-switched GSM, priorities for their Hierarchical Cell Structure (HCS) canbe defined, with GSM or UMTS as the preferred layer.

Causes for emergency handoverare

uplink / downlink quality

uplink / downlink strength

distance or

forced (directed retry, O&M intervention, preemption).

Although the link quality within the serving cell may be sufficient, the better cellhandoveris triggered if there is available a neighbor cell with a better receive level(power budget handover). Consequently there is a benefit in terms of overall networkperformance as a call in a better cell causes less interference.

An handover due to sufficient UMTS coverageis triggered by the system if certain

thresholds (RSCP received signal code power from UMTS, Ec/No quality forUMTS cells) are reached.


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Mobile (MS/UE)

2G-3G-MSCA

Um

Abis

BTS

BSC

GSM Cell

Uu

Iub

Node-B

UMTS Cell

Iu (cs)RNC

Handover from GSM to UMTS

Fig. 3 Handover from GSM to UMTS


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2.2 SBS implementation

Message Flow

The BSS initiates a handover to UMTS by including the UMTS target cells in theHandover Required message.

The 3G-MSC performs the UMTS service mapping (for speech and data) andtranscoder mapping as well as the GSM to UMTS cipher key conversion. The 3G-MSC generates and sends the Iu Relocation Request message to the UMTS radionetwork system RNS.

After having received the Iu-Relocation-Request-Ack message, the 3G-MSC sendsthe Handover Command to the BSS, which sends the RI-HO-Command message

(Radio Interface to UTRAN handover command) to the UE/MS.

After the UE/MS has performed the radio access to the UMTS cell, the RNS sendsthe Iu Relocation Detect message to the 3G-MSC. After the UE/MS has completedthe handover and is successfully communicating with the target RNS, it sends theRadio Resource Control Handover Complete message to the target RNS. Thetarget RNS sends the Iu Relocation Complete message to the 3G-MSC. Then the3G-MSC sends the Clear Command message to the source BSS. The source BSSreturns the Clear Complete message to the 3G-MSC.


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UE / MS UE / MS

RNS-A 3G-MSC-A BSS-B

Handover-

RequiredIu-Relocation-

Request

RI-Handover-

Command

Iu-Relocation-

Request-Ack Handover-

Command

Iu-Relocation-DetectRRC-HO-

CompleteIu-Relocation-

CompleteClear-

Command

Clear-

Complete

Fig. 4 Message Flow for Handover from GSM to UMTS


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2.3 GSM to UMTS Handover Types

2.3.1 Better Cell Handover from GSM to UMTS cell

The main objective of the "Better Cell HO (Power Budget HO)" is to minimize the RFpower needed for communication between the mobile station MS/UE and the network(base station). Minimizing the RF power reduces the radio interference in the wholenetwork and increases the battery life of the MS/UE.

The better cell HO decision (power budget HO decision) concerning UMTS neighborcells is the same than GSM neighbor cells except an additional adjustment valuewhich is needed to adapt the UMTS measurement values to the GSM valuesbecause of a difference in measurement method.

UMTS neighbor cells are only taken into consideration if the following conditions aremet:

MS/UE is UMTS capable

Service HO Information Element (in the ASSIGNMENT REQUEST or HANDOVERREQUEST) is not set to Handover to UTRAN or cdma2000 should not beperformed or "Handover to UTRAN or cdma2000 shall not be performed

HO_from_GSM_to_UMTS is enabled (EUHO)

Better_Cell_HO_to_UMTS is enabled (EUBCHO)

FDD_REP_QUANT == 0 (i.e. RSCP)

Flag "ASCI TALKER" is not set to TRUE

Notes

The GSM system internal Power-Budget HO is not modified!

ASCI is a GSM feature and not supported by the UMTS system. The Informationabout ASCI is sent from the BSC to the BTS in the IE Channel Options of the

Channel Activation message and of the "Forced HO Request" message.Handover to cdma2000 is not supported.


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Notes:

1. (s) denotes serving cell, (n) denotes neighbor cell

2. UMTS_ADJUST(n) is a parameter which is introduced for GSM to UMTShandover and not used for GSM to GSM handover. It is an inter-systemadjustment parameter in order to have the flexibility to adjust theRXLEV_NCELL(n) of the UMTS neighbor cells (n) to the RXLEV_DL of the GSMserving cell.

3. For UMTS neighbor cells (n), the UMTS measurement quantity RSCP, which theMS/UE reports in its Measurement Report, is used for RXLEV_NCELL(n).

4. Not new in the above equations are all another parameters (already in use forGSM-internal HO):

RXLEV_NCELL(n) is the neighbor cell received level (GSM or UMTS neighbor

cell) measured by the MS/UE.

RXLEV_DL is the GSM serving cell received level (downlink) measured by theMS/UE.

PWR_C_D is the difference between the maximum downlink RF power permittedin the GSM serving cell and the actual downlink power due to the BSS powercontrol.

RXLEVMIN(n) defines the minimum received level which is required to perform ahandover to the neighbor cell (GSM or UMTS neighbor cell).

MS_TXPWR_MAX(s) is the maximum RF TX power an MS/UE is permitted to use

on a traffic channel in the GSM serving cell.

MS_TXPWR_MAX(n) is the maximum RF TX power an MS/UE is permitted to usein the neighbor cell (GSM or UMTS neighbor cell).

P(s) is the maximum TX power capability of the MS/UE in the GSM serving cell.

'P(n) is the maximum TX power capability of the MS/UE in the neighbor cell (GSMor UMTS neighbor cell).

HOMARGIN(n) is a threshold which can be used to prevent handover oscillationsbetween the serving GSM cell and neighbor cells (GSM or UMTS neighbor cell).

PL is the HCS priority value of the GSM serving cell.PRIO_NCELL is the HCS priority value of the neighbor cell (GSM or UMTSneighbor cell).

In order to perform the handover, the HCS priority of the neighbor cell must beequal to or higher than the priority of the GSM serving cell; i.e. the priority valuePRIO_NCELL of the neighbor cell must be equal to or smaller than the priorityvalue PL of the GSM serving cell.


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2.3.2 Sufficient UMTS coverage HO from GSM to UMTS

The main objective of the GSM to UMTS "Sufficient UMTS coverage HO" is toperform a handover to the UMTS system as soon as possible, i.e. as soon as theUMTS measurement quantity (RSCP or Ec/No for FDD cells, RSCP for TDD cells)exceeds a certain "sufficient" threshold in order to direct as much traffic as possibleto areas which offer "sufficient" UMTS coverage.

Sufficient UMTS Coverage HO has a relatively high priority (less than emergency HObut higher than power budget HO).

UMTS neighbor cells are only taken in consideration if the following conditions aremet:

1. MS/UE is UMTS capable

2. Service HO Information is not set to Handover to UTRAN or cdma2000 shouldnot be performed or "Handover to UTRAN or cdma2000 shall not be performed

3. HO_from_GSM_to_UMTS is enabled (EUHO)

4. UMTS_Sufficient_Coverage_HO is enabled (EUSCHO)

5. Flag "ASCI talker" is not set to TRUE

The condition for a "Sufficient UMTS coverage" HO from GSM to UMTS is:

RXLEV_NCELL(n) > UMTS_SUFFICIENT(n) + Max (0, Pa)

Pa := (MS_TXPWR_MAX(n) - P(n))

UMTS_SUFFICIENT_RSCP(n)and UMTS_SUFFICIENT_Ec/No(n)define the"sufficient" threshold which is required to perform a handover to the neighbor UMTScell. The kind of threshold used is administered with the parameter FDDQTY.


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2.3.3 Imperative HO from GSM to UMTS

The BTS initiates an imperative handover in the same way as for a GSM internalhandover. Imperative HO is done if the connection run the risk of connection lossbecause of bad receive level or distance (in the servingcell).

The imperative (emergency) HO causes which are currently used for GSM-systeminternal handovers are used in the same way for UMTS handover:

uplink/downlink quality

uplink/downlink strength

distance

Imperative HO to UMTS cells is enabled / disabled by the parameter EUIMPHO.

For an imperative HO, the UMTS neighbor cells have to be taken into account for thetarget cell list generation.

2.3.4 Mobile speed-sensitive HO from GSM to UMTS

Within the current concept of "Mobile Speed Sensitive HO", a timer of durationHOMDTIME is used to distinguish "fast moving" and "slow moving" mobile stations.The timer is started when the MS/UE crosses the border of the microcell. If the

MS/UE leaves the cell within HOMDTIME, the MS/UE is considered to be "fastmoving". If the MS/UE is still located within the cell after duration HOMDTIME, theMS/UE is considered "slow moving".

This means within the current concept of "Mobile Speed Sensitive HO", the Power-Budget HO is penalized for t < HOMDTIME by adding a penalization valueHOMSOFF to the Power-Budget equation and by substituting the HCS cell priorityPRIO_NCELL to a low value PPLNC:

For GSM cells:

PRIO_PBGT = PBGT - (HOMARGIN + HOMSOFF)PRIO_NCELL is substituted by PPLNC.

For UMTS cells:

PRIO_PBGT = PBGT - (HOMARGIN + HOMSOFF + UMTS_ADJUST)

PRIO_NCELL is substituted by PPLNC.


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After timer expiry, i.e. for t >= HOMDTIME, the above Power-Budget penalization iscompensated with HOMDOFF and the HCS cell priority is set back to the originalvalue PRIO_NCELL (i.e. a handover is possible for the "slow moving" MS/UE):

For GSM cells:

PRIO_PBGT = PBGT - (HOMARGIN + HOMSOFF - HOMDOFF)

HCS cell priority PPLNC is set back to PRIO_NCELL.

For UMTS cells:

PRIO_PBGT = PBGT - (HOMARGIN + HOMSOFF - HOMDOFF + UMTS_ADJUST)

HCS cell priority PPLNC is set back to PRIO_NCELL.

For Sufficient UMTS coverage HO, the hoMarginDelayTimer is started when theabove "Sufficient UMTS Coverage" condition is met.

The "Sufficient UMTS coverage" HO is performed for a "slow moving" MS/UE, i.e. fora MS/UE for which the "Sufficient UMTS coverage" condition is still met for t >=HOMDTIME.

The "Sufficient UMTS coverage" HO is not performed for a "fast moving" MS/UE, i.e.for a MS/UE for which the "Sufficient UMTS Coverage" condition is violated beforethe timer HOMDTIME expires.

2.3.5 Directed retry from GSM to UMTS

During call setup the BSC indicates that a (forced) HO is necessary and sends aForced HO Request message to the BTS.

The Forced HO Request contains the IE Service Handover received from the ASSIGNMENT REQUEST message and the IE Channel Options. The IE "ServiceHandover" specifies whether a handover to UMTS should, should not or shall not be

performed. The IE Channel Options contains information concerning ASCI-Talker.The BTS answers the Forced HO request if possible (TCL available) with an "Inter-cell HO Condition Indication" message which contains the Target Cell List (TCL). TheBTS sorts the TCL as for an "Imperative HO" taking into account the setting of the IE"Service Handover".

It is possible to enable/disable the Directed Retry to UMTS via the parameterEUSDCHO. If set to FALSE, the BTS does not include UMTS cells into the TCL anddoes not initiate a handover to UMTS for a MS/UE which is on a SDCCH.


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2.4 Generation of target cell list

The TCL contains the neighbor cells which are handover candidates. The target celllist is part of the message Handover Condition Indication which is sent from BTS toBSC.

UMTS target cells are only taken into consideration if:

HO from GSM to UMTS is enabled,

the flag ASCI talker is FALSE,

the IE Service Handover is not set to "Handover to UTRAN or cdma2000 shallnot be performed.

Remarks

For HO cause "Sufficient UMTS Coverage" the TCL only contains UMTS target cells.

For "Imperative HO to UMTS", the UMTS target cells are sorted in the TCL in thesame way as GSM target cell lists. If EC/No is used, UMTS cells are sorted after theGSM cells.

For "Better Cell HO to UMTS" and REPQTY=RSCP, the UMTS target cells are sortedin the TCL in the same way as GSM target cell lists.

The sorting of the UMTS target cells relative to GSM target cellsdepends on theService Handover Information.

If Service Handover is set to

"HO to UTRAN or cdma2000 shall not be performed": no UMTS cell in TCL.

"HO to UTRAN or cdma2000 should not be performed": for imperative HO theUMTS cells are sorted after the GSM cells; in case of other HO reasons (e.g.Power Budget) no UMTS cell in the TCL.

"HO to UTRAN or cdma2000 should be performed": the GSM cells are sorted afterthe UMTS sub-list.

If Service Handover is not set, a mixed TCL list is generated from which the "bestcell" is taken, no matter if it belongs to UTRAN or GERAN. A mixed TCL isaccording to HCS priority and PRIO_PBGT.


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2.4.1 Sorting of UMTS and GSM Cells which have different HCSpriority

UMTS cells and GSM cells internally are sorted according to their HCS priority. Thecell with the highest HCS priority is sorted to the top position of the TCL sub-list. If theHCS priority is the same, GSM cells are sorted in the same way as for a GSM-internal HO.

In the following cases, GSM and UMTS cells in a "mixed" TCL, i.e. in a TCLcontaining both GSM and UMTS cells, are not sorted together according to HCSpriority:

"Better Cell" HO

If FDD_REP_QUANT = 1: Only the GSM cells are sorted according to HCS priority.UMTS cells are not included in the TCL.

If MS/UE is on SDCCH and EUSDCHO = FALSE: Only GSM cells are sortedaccording to HCS priority. UMTS cells are not included in the TCL for this MS/UE.

If ASCI_TALKER = TRUE: Only GSM cells are sorted according to HCS priority.UMTS cells are not included in the TCL for this MS/UE.

"Sufficient UMTS Coverage" HO

TCL only contains UMTS cells which are sorted according to HCS priority:

If MS/UE is on SDCCH and EUSDCHO = FALSE: The "Sufficient UMTS coverage

HO" is disabled for this MS/UE.If ASCI_TALKER = TRUE: The GSM to UMTS "Sufficient UMTS coverage HO" isdisabled for this MS/UE.

"Imperative"HO

If MS/UE is on SDCCH and EUSDCHO = FALSE: The "Sufficient UMTS coverageHO" is disabled for this MS/UE.

If ASCI_TALKER = TRUE: The GSM to UMTS "Sufficient UMTS coverage HO" isdisabled for this MS/UE.


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MN1789EU12MN_0001


2.5 BSC Database parameters

In addition to a "main flag" to enable GSM to UMTS HO, there are separate flags toenable different types of GSM to UMTS handover.

Parameter Object Range Description

EUHO HAND TRUE, FALSE(default)

Enable Handover from GSM to UMTS

EUBCHO HAND TRUE, FALSE(default)

Enable Better Cell HO to UMTS

EUSCHO HAND TRUE, FALSE(default)

Enable Sufficient Cell Coverage HO to UMTS

EUIMPHO HAND TRUE, FALSE(default)

Enable Imperative HO to UMTS

EUSDCHO BSC TRUE, FALSE(default)

Enable Directed Retry from GSM to UMTS


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Collecting the UMTS cell measurements and the results processing is described withthe parameters:

Parameter Object Range (Default) Description

PUREBBSIG44CONF

BTS TRUE, FALSE, NULL Indication if BTSone isequipped with BBSIG44exclusively to support UMTSHO, or not.

FDDREPQTY BTS 0 (RSCP, def.), 1(Ec/N0)

Reporting quantity for UTRANFDD cells

QSRHC BTS 0 (< -98 dB), 1 (-54 dB), 15 (never,def.)

Threshold which enables thesearch for 3G cells for HOmeasurements on other RATs

QSRHCINI BTS QSEARCHI (0, def.),Always (1)

Qsearch values which is usedbefore QSearchC has beenreceived

FDDMURREP,TDDMURREP

BTS 0 .. 3 Number of FDD / TDD cells tobe included in the meas. report

FDDQ,TDDQO

BTS 0 (- infinity), 1 (- 28 dB),2 (- 24 dB) .. 15 (28 dB)

Offset applied to level of FDD /TDD serving cell (def. 8 0 dB)

FDDQMI BTS MDB13,MDB14,MDB20 (def.)

Signal Ec/No is higher than thisminimal threshold

MSTXPMAXUMTS

BTS 0 (43 dBm, def.), 1 (41dBm) .. 19 (5 dBm)

Max. TX power for MS/UE inUMTS cell

UMTSSRHPRI BTS TRUE/FALSE (def.) UMTS Search Priority indicatesif MS can search for 3G cellswhen BSIC decoding isrequired (i.e. if the searchingtime can be longer than

normal- 13s instead of 10s)


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MN1789EU12MN_0001


To define criteria for handover to 3G cells, the following parameters are available:

Parameter Object Range (Default) DescriptionUADJ ADJC

3G

0 (-63 dB) ..63 (0dB, default) .. 126(63 dB)

For Better Cell HO: adjustment of levelfor UMTS cell to level of GSM servingcell (63 def.)

USRCP ADJC

3G

0 (RSCP < -115dBm) .. 63 (>=53dBm);

Threshold required for sufficientUMTS cell coverage (FDD:FDDREPQTY=0 required)

USECNO ADJC

3G

0 (Ec/N0 < 24 dB) ..49 (Ec/N0 >= 0 dB)

Threshold required for sufficientUMTS cell coverage (FDD:FDDREPQTY=1; 23 def.)

UMECNO ADJC3G

0 (Ec/N0 < 24 dB) ..49 (Ec/N0 >= 0 dB)

Min. Level required to include a UMTScell in the target cell list for ImperativeHO (FDDREPQTY=1 req; 19 def.)

TGTCELL

TGTFDD/

ADJC/ADJC3G

Path name This parameter indicates to which BSC/technology the adjacent cell belongs

PLNC ADJC

3G

0 .. 15 Priority layer of the adjacent 3G cell

RXLEVMINC ADJC

3G

0 ( -49dBm)

Minimal received signal level the adjc.UMTS cell must provide to beregarded as suitable target cell for HO

TINHFAIHO ADJC

3G

1 .. 254 (seconds) The BTS timer is started whenMAXFAILHO has been reached. Whilethe timer is running, the correspondingcell is excluded from the target cell list.

MICROCELL ADJC

3G

TRUE, FALSE(def.)

To enable Mobile Speed SensitiveHandover

HOM ADJC

3G

0 (- 63 dB), 1 (-62dB) .. 69 (6 dB,def.) .. 126 (+63dB)

Threshold to prevent repetitive HO ifcaused by RX level or power budget

HOMDTIME ADJC3G

0 (def.) .. 255(SACCHmultiframes)

Time an immediate HO request isdelayed when the serving cell edge isreached

HOMSOFF ADJC3G

0 (def.) .. 127 (indB)

Static offset for HO margin (during run-time of HOMDTIME)


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PPLNC ADJC3G

0 (def.) .. 15 Temporary penalty priority layer of theadjacent UMTS cell

HOMDOFF ADJC

3G

0 (def.) .. 127 (dB) Dynamic offset for reduction of HOmargin after HOMDTIME has expired

To define 3G FDD and TDD neighbor cells respectively, the following parameters andobjects are available:


CELLGLID TGTFDD MCCMNCLAC-CI Cell Global ID

RNCID TGTFDD 0 .. 4095 RNC identifier

FDDARFCN TGTFDD 412 .. 10838 Absolute radio frequency carrierno. (FDD)

FDDSCRMC TGTFDD 0 .. 511 Primary scrambling code

FDDDIV TGTFDD Diversity (1),No_Diversity (0)

Indicates if diversity is used (ornot) in FDD cell


CELLGLID TGTTDD MCCMNCLAC-CI Cell Global ID

RNCID TGTTDD 0 .. 4095 RNC identifier

BNDWIDTDD TGTTDD 0 (HCR), 1 (LCR); Bandwidth TDD cell

TDDARFCN TGTTDD 9262 .. 10113 Absolute radio frequency carriernumber. (TDD)

TDDCPAR TGTTDD 0 .. 127 TDD cell parameter

TDDSYNCCAS TGTTDD SYNC1, SYNC2 Synchronization case for TDDcell

TDDDIV TGTTDD Diversity (1),No_Diversity (0)

Indicates if diversity is used (ornot) in TDD cell


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2.5.1 Restrictions

ASCI service is the GSM feature and not supported by the UMTS system. Therefore,a handover from GSM to UMTS is not performed for an ASCI talker.

Handover to cdma2000 is not supported.

Documents

05 Mn1789eu12mn 0001 Gsm Umts Interworking