3G-Mobility-Idle-Mode

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Module 13JK10049AAAAZZZZA Edition 1

Section 5Mobility Idle Mode

9300 W-CDMAUA06 R99 Algorithms Description

TMO18045 Edition 1


9300 W-CDMA UA06 R99 Algorithms DescriptionMobility Idle Mode

5 2

Blank Page



5 3

Module Objectives

Upon completion of this module, you should be able to:

Describe PLMN selection and associated parameters

Describe Cell selection and associated parameters in Idle Mode

Describe Cell reselection and associated parameters in Idle Mode

Case of mobility in Connected Mode in Cell_FACH, Cell_PCH or URA_PCH



5 4

Module Objectives [cont.]



5 5

Table of Contents

Switch to notes view!



5 6

Table of Contents [cont.]

Switch to notes view!



5 7

1 Network Selection



5 8

1 Network Selection

1.1 PLMN Selection

Describe Cell reselection and associated parameters

MCC MNC MSIN

mobileCountryCode (Operator)

mobileNetworkCode (Operator)

mobileCountryCode (RNC)

mobileNetworkCode (RNC)

mobileCountryCode (CsCoreNetworkAccess)

mobileNetworkCode (CsCoreNetworkAccess)

mobileCountryCode (PsCoreNetworkAccess)

mobileNetworkCode (PsCoreNetworkAccess)

mobileCountryCode (FDDCell)

mobileNetworkCode (FDDCell)

MIB / P

-CCPCH

Preferred PLMN List Forbidden PLMN List



5 9

2 Cell Selection in Idle Mode



5 10


2.1 Cell Selection Criteria

Srxlev > 0

CPICH_RSCP > qRxLevMin + Pcompensation

P-CPIC

H

S Criteria

AND

qQualMin

qRxLevMin

Squal > 0

CPICH_Ec/No > qQualMin

FDDCCe

ll

FDDCell

CellSelectionInfo



5 11


2.2 UE Power Compensation

NodeB

RNC

FDDCell

CellSelectionInfo

RadioAccessService

DedicatedConf

PowerConfClass

Pcompensation=

max (sibMaxAllowedUlTxPowerOnRach P_MAX, 0)

Srxlev > 0

CPICH_RSCP > qRxLevMin + Pcompensation

+21 dBm4

+24 dBm3

+27 dBm2

+33 dBm1

P_MAXUE Class

qRxLevMinsibMaxAllowedUlTxPowerOnRach

powerConfId



5 12

3 Cell Reselection in Idle Mode Principles



5 13


3.1 General Concept

HM not detectedCell Reselection after tReselection

Higher priority is favored

HM detectedCell Reselection after tReselection * speedDependScalingFactor

Lower priority is favored

P1

P2 P2 P2

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6

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P3 P3 P3 P3 P3P3

2 different 3GPP UE algorithms

Classical for mono-layer network

Hierarchical Cell Structure (HCS) algorithm HCS Priority for Serving cell and Neighboring cells are introduced (between 0 and 7)

Both algorithms steps:

Define which type of neighboring cells have to be measured (intra-freq, inter-freq, inter-RAT)

Check if measured cells are eligible to cell reselection

Rank the eligible cells to eventually perform cell reselection

Different behaviors in case: HCS is used / NOT used

High-Mobility Detection (HMD) is detected / NOT detected



5 14


3.2 Mobility in Idle mode, Cell_FACH, Cell_PCH and URA_PCH

Cell SelectionS criterion

Cell Reselection without HCS

Measurements Rules without HCS

Cell Ranking without HCSusing High Mobility Detection

Level + QualityR criteria

Cell Reselection with HCS

Measurements Rules with HCS

using High Mobility Detection

Quality Level Threshold H Criterion

Cell Ranking with HCSusing High Mobility Detection

HCS is usedHCS is not used

Level + QualityR criteria

Cell Filteringusing HCS Priority



5 15


3.3 Idle Mode Neighboring List

sib11AndDchNeighbouringFddCellAlgo

(FDDCell)

sib11OrDchUsage

(UMTSFddNeighbouringCell)

(GsmNeighbouringCell)

SIB11 /

P-CCPC

H

Serving

Cell

Max 48 cells

SIB11 Neighboring List

UMTSFddNeighbouringCell List

GsmNeighbouringCell List

FDDCell Neighboring List

intra-frequency FDDCells

inter-frequency FDDCells

GSM Cells



5 16


3.4 Cell Reselection Eligibility Criteria

UMTSFddNeighbouringCell

Srxlev > 0Squal > 0

> > + PcompensationCPICH_Ec/No qQualMin (UMTSFddNeighbouringCell) qRxLevMin(UMTSFddNeighbouringCell)

CPICH_RSCPAND

GSMNeighbouringCell

QRxLeavMeas > qRxLevMin (GSMNeighbouringCell) + Pcompensation

Srxlev > 0

Max(MaxAllowedUlTxPower - P_max, 0)

(GSMNeighbour/GsmCell)

Max(MaxAllowedUlTxPower - P_max, 0)

(UmtsNeigbouringRelation)



5 17


3.5 High Mobility Detection

Nb of Reselection > nCrduring tCrMax

UE not in High Mobility state

UE enters High Mobility state

Nb of Reselection



5 18

4 Cell Reselection in Idle Mode without HCS



5 19

4 Cell Reselection in Idle mode without HCS

4.1 Measurements Rules without HCS

sIntraSearch

sInterSearch

sSearchRatGsm

isHcsUsed = FalsesSearchHcs

sHcsRatGsm

Intra-frequency No measurement

Intra-frequency Inter-frequency Inter-frequency

Intra-frequency Inter-frequency

GSM

Inter-frequency GSM

Srxlev

sInterSearch sIntraSearch sSearchRatGsm

sSearchHcs

sHcsRatGsm

Squal

FDDCell

CellSelectionInfo



5 20


4.2 Level Ranking Criterion without HCS

qHyst1 (CellSelectionInfo)

UMTSFddNeighbouringCell

GSMNeighbouringCell

CPICH_RSCP qOffset1sn (UMTSFddNeighbouringCell)CPICH_RSCPRLs = +

RL criterion for Serving Cell RL criterion for FDD Neighboring Cell

RLn =

FDDCell

RxLev qOffset1sn (GSMNeighbouringCell)RLn =

RL criterion for GSM Neighboring Cell


qOffset1sn (UmtsNeighbouringRelation)

qOffset1sn (GsmNeighbouringCell)



5 21


4.3 Quality Ranking Criterion without HCS

RQn = RQs = +CPICH_Ec/No CPICH_Ec/NoqHyst2 (CellSelectionInfo) qOffset2sn (UMTSFddNeighbouringCell)

RQ criterion for Serving Cell RQ criterion for Neighboring Cell

FDDCell UMTSFddNeighbouringCell


qOffset2sn (UmtsNeighbouringRelation)



5 22


4.4 Cell Ranking Algorithm

FDDCell

CPICH_Ec/No CPICH_RSCP

Best cell is a ..?

Best GSMCellis reselected

GSMCell

Best FDDCellafter First Ranking

is reselected

Best FDDCellafter Second Ranking

is reselected

qualMeas = ..?

Eligible CellsFirst Ranking RL

(CPICH_RSCP & RxLev)

Second Ranking RQ

(CPICH_Ec/No)

qualMeas (cellSelectionInfo)



5 23


4.5 Triggering Algorithm

UMTSFddNeighbouringCellInter-freq

UMTSFddNeighbouringCellIntra-freq

GSMNeighbouringCell

ServingFDDCell

tReselection (UE not in High Mobility)tReselection x speedDependScalingFactorTReselection (UE in High Mobility)

tReselectionx interRatScalingFactorTReselection(UE not in High Mobility)

tReselectionx speedDependScalingFactorTReselectionx interRatScalingFactorTReselection(UE in High Mobility)

tReselection x interFreqScalingFactorTReselection (UE not in High Mobility)tReselection x speedDependScalingFactorTReselection x interFreqScalingFactorTReselection (UE in High Mobility)

speedDependScalingFactorTReselection

(CrMgt)

tReselectioninterFreqScalingFactorTReselectioninterRatScalingFactorTReselection

(CellSelectionInfo)

Cell reselection triggered if

the target cell remains best-ranked during more than tReselection sec

the UE has been camping on the current serving cell since at least 1 sec

For R5 UE, tReselection is replaced by



5 24

Exercise: Multi-Layer Cell Structure, HCS not used

Neighb.MC

Neighb.MA Neighb.MB

Serv.mc

Macro FDDcells F2

Micro FDDcells F1

Neighb.GC

Neighb.GA Neighb.GBMacro GSMcells

Neighbo.mbNeighbo.ma

20-73Neighboring cell GC

20-80Neighboring cell GB

20-98Neighboring cell GA

100-85-4Neighboring cell MC

100-89-5Neighboring cell MB

100-99-9Neighboring cell MA

00-104-10Neighboring cell mb

00-118-21Neighboring cell ma

44-108-12Serving cell mc

qOffset2sn(dB)

qHyst2(dB)

qOffset1sn(dB)

qHyst1(dB)

CPICH_RSCP (dBm)

CPICH_Ec/No (dB)

Cell



5 25

Exercise: Multi-Layer Cell Structure, HCS not used [cont.]

Assumptions UE class 3

qualMeas = qualMeasEcno

qQualmin (Serving and Neighboring Cell 3G) = - 16 dB

qRxLevMin (Serving and Neighboring Cell 3G) = - 115 dBm

qRxLevMin (Neighboring Cell 2G) = - 104 dBm

sibMaxAllowedUlTxPowerOnRach = 24 dBm

maxAllowedUlTxPower (Neighboring Cell 3G) = 24 dBm

maxAllowedUlTxPower (Neighboring Cell 2G) = 33 dBm sIntraSearch = 8dB sInterSearch = 6dB sSearchRatGSM = 4dB sSearchHcs = 0dB sHcsRatGsm = 0dB

isHcsUsed = False

Question: which is the cell reselected by the UE ?



5 26

5 Cell Reselection in Idle Mode with HCS



5 27


5.1 Principles

hcsPrio (hcsCellparam)

hcsPrio (UmtsNeighbouringHcsCellparam)

hcsPrio (GsmHcsCellparam)

Each cell is assigned an HCS Priority value between 0 and 7

0 = lowest priority

7 = highest priority

P1

P3

HM not detected Higher priority is favored

HM detected Lower priority is favored

P2 P2

P3 P3 P3

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5.2 Measurements Rules with HCS in Low Mobility

isHcsUsed (FDDCell) = True UE not in High Mobility state


hcsPrion >= hcsPrios


hcsPrion > hcsPrios

All Intra-frequency All Inter-frequency

GSM hcsPrion >= hcsPrios

No measurement

All GSM

Srxlev

sInterSearch sIntraSearch Squal

sSearchHcs

Srxlev

Squal

sHcsRatGsm

sSearchRatGsm sLimitSearchRat

sLimitSearchRat

(HcsCellParam)



5 29


5.3 HCS Quality Level Threshold Criterion

Qmeasn qHcsnHn =

qHcss

NeighbouringCellhcsPriorityn = hcsPrioritys

NeighbouringCellhcsPriorityn hcsPrioritys

Qmeasn qHcsnQmeassHs =

H criterion for Serving CellH criterion for FDD or GSM Neighboring Cellof same HCS priority as Serving cell

Hn =

FDDCellhcsPrioritys

H criterion for FDD or GSM Neighboring Cellof different HCS priority than Serving cell

qHcs (hcsCellparam)

qHcs (UmtsNeighbouringHcsCellparam)

qHcs (GsmHcsCellparam)



5 30


5.4 Measurements Rules with HCS in High Mobility

UE in High Mobility state


hcsPrion



5 31


5.5 Level and Quality Ranking Criteria with HCS

qHysts

NeighbouringCellhcsPriorityn = hcsPrioritys

NeighbouringCellhcsPriorityn hcsPrioritys

QmeassRs = +

R criterion for Serving Cell

R criterion for FDD or GSM Neighboring Cellof same HCS priority as Serving cell

FDDCellhcsPrioritys

Qmeasn qOffsetsns,nRn =

R criterion for FDD or GSM Neighboring Cellof different HCS priority than Serving cell

Qmeasn qOffsetsns,nRn =



5 32


5.6 HCS Cell Filtering in Low Mobility

UE is in High Mobility

state ?

Eligible Cellsaccording to S criteria

Candidate Cells Ranking

R criteria

yes

At least one cell has

H criterion >=0 ?

no

Keep all neighboring FDD and GSM cells

of the highest hcsPriority as candidates

among those having H criterion >=0

yes

Keep all neighboring

FDD and GSM cellsas candidates

without ordering them

no

See next page



5 33


5.7 HCS Cell Filtering in High Mobility

Keep all neighboring FDD and GSM cells of the highest hcsPriority as candidates

among those having1. hcsPriorityn < hcsPrioritys

2. H criterion >=0

Candidate Cells Ranking

R criteria

UE in High Mobility

Keep all neighboring FDD and GSM cells of the lowest hcsPriority as candidates

among those having 1. hcsPriorityn >= hcsPrioritys

2. H criterion >=0

not empty list

Keep all neighboring FDD and GSM cellsas candidates

without ordering them

empty list

not empty list

empty list



5 34


5.8 Cell Ranking Algorithm

FDDCell

CPICH_Ec/No CPICH_RSCP

Best cell is a ..?

Best GSMCellis reselected

GSMCell

Best FDDCellafter First Ranking

is reselected

Best FDDCellafter Second Ranking

is reselected

qualMeas = ..?

First Ranking RL

(CPICH_RSCP & RxLev)

Second Ranking RQ

(CPICH_Ec/No)

Candidate NeighboringFDD and GSM cells for

Cell Reselection

Same Ranking as without HCS



5 35


5.9 Triggering Algorithm

tReselection (CellSelectionInfo)

interFreqScalingFactorTReselection (CellSelectionInfo)

interRatScalingFactorTReselection (CellSelectionInfo)

UMTSFddNeighbouringCellInter-freq

UMTSFddNeighbouringCellIntra-freq

GSMNeighbouringCell

ServingFDDCell

tReselection (UE not in High Mobility)tReselection x speedDependScalingFactorTReselection (UE in High Mobility)

tReselectionx interRatScalingFactorTReselection(UE not in High Mobility)

tReselection x speedDependScalingFactorTReselectionx interRatScalingFactorTReselection(UE in High Mobility)

tReselection x interFreqScalingFactorTReselection (UE not in High Mobility)tReselection x speedDependScalingFactorTReselection x interFreqScalingFactorTReselection (UE in High Mobility)

speedDependScalingFactorTReselection (CrMgt)

Same triggering as without HCS



5 36

Exercise: Multi-Layer Cell Structure, HCS used

Neighb.MC

Neighb.MA Neighb.MB

Serv.mc

Macro FDDcells F2

Micro FDDcells F1

Neighb.GC

Neighb.GA Neighb.GB

Macro GSMcells

Neighbo.mbNeighbo.ma

0

0

0

0

0

qOffset2sn(dB)

0

0

0

1

1

1

2

2

2

hcsPriority

-1000-73Neighboring cell GC

-1000-80Neighboring cell GB

-1000-98Neighboring cell GA

-140-85-4Neighboring cell MC

-140-89-5Neighboring cell MB

-140-99-9Neighboring cell MA

-100-104-10Neighboring cell mb

-100-118-21Neighboring cell ma

-1044-108-12Serving cell mc

qHcs(dB)

qHyst2(dB)

qOffset1sn(dB)

qHyst1(dB)

CPICH_RSCP (dBm)

CPICH_Ec/No (dB)

Cell

hcsPriority = 0

hcsPriority = 1

hcsPriority = 2



5 37

Exercise: Multi-Layer Cell Structure, HCS used [cont.]

Assumptions UE class 3

qualMeas = qualMeasEcno

qQualmin (Serving and Neighboring Cell 3G) = - 16 dB

qRxLevMin (Serving and Neighboring Cell 3G) = - 115 dBm

qRxLevMin (Neighboring Cell 2G) = - 104 dBm

sibMaxAllowedUlTxPowerOnRach = 24 dBm

maxAllowedUlTxPower (Neighboring Cell 3G) = 24 dBm

maxAllowedUlTxPower (Neighboring Cell 2G) = 33 dBm sIntraSearch = 8dB sInterSearch = 6dB sSearchRatGSM = 4dB sSearchHcs = 0dB sHcsRatGsm = 0dB

isHcsUsed = True sLimitSearchRat = 4dB temporaryOffest = parameters not used

Question 1: which is the cell reselected by the UE if in High Mobility ?

Question 2: which is the cell reselected by the UE if in Low Mobility ?



5 38

6 Cell reselection in non-DCH Connected Mode



5 39


6.1 SIB 4 and SIB 12 Broadcast

SIB 4: Se

rving Ce

ll

re-selection p

arame

ters broa

dcast

isDynamicSibAlgoWithSbAllowed(RadioAccessService)

SIB11+

DCHDCH

SIB11+

DCH

DCH

DCH

DCH

SIB11+

DCH SIB11+

DCH

SIB11+

DCH

DCH

DCH

DCH

SIB11+

DCHDCH

SIB11+

DCH

SIB11+

DCH

SIB11+

DCHDCH

DCH

DCHDCH

DCH

SIB11+

DCH

ServingFDDCell

DCH

SIB11+

DCH

DCH

DCH

SIB11+

DCHDCH

DCH

Cell_FACHCell_PCHURA_PCH

SIB 12

: Neig

hboring

Cells

re-se

lection p

arame

ters broadcast

sib4Enable (FDDCell)sib12Enable (FDDCell)



5 40


6.2 Sib3 / Sib 11 Parameters & Objects

UmtsNeighbouring

UmtsNeighbouringRelation

CellSelectionInfo

RNC

NodeB

FddCell

FachMeasOccasionInfo

CrMgt

HcsCellParam

UmtsFddNeighbouringCell

UmtsNeighbouringHcsTemporaryOffsets

UmtsNeighbouringHcsCellParam

New objects

Existing related parameters

cellAccessrestriction



5 41


6.3 SIB4 Parameters & Objects

CellSelectionInfoConnectedMode

NodeB

FddCell

New objects


FachMeasOccasionInfo

CrMgt

HcsCellParam

cellSelectReselectInfoPchFach

cellAccessRestrictionConnectedMode

tReselectionqHyst1qHyst2

R99/R4 UEs

R5/R6 UEs

tReselectionPchtReselectionFach

qHyst1PchqHyst1FachqHyst2PchqHyst2Fach



5 42


6.4 SIB 12 Parameters & Objects UMTS FDD Neighbor

FddNeighCellSelectionInfoConnectedMode

UmtsNeighbouringRelation

UmtsNeighbouring

RNC

NodeB

Fddcell

UmtsFddNeighbouringCell

UmtsNeighbouringHcsTemporaryOffsets

UmtsNeighbouringHcsCellParam

New objects


qQualMin

qRxlevMin

qOffset1sn

qOffset2sn

maxAllowedUlTxPower

hcsPrio

qHcs



5 43


6.5 SIB 12 Parameters & Objects GSM Neighbor

GsmCellSelectionInfoConnMode

GSMCell

GSMNeighbour

RNC

NodeB

Fddcell

GsmNeighbouringCell

GsmHcsTemporaryOffsets

GsmgHcsCellParam

New objects


qRxlevMin

qOffset1sn

hcsPrio

qHcs

GSMCellCellSelectionInfoCMForGsmCell

maxAllowedUlTxPower



5 44

Exercise

By Respecting the flowing strategy fill in tables in next pages with the

appropriate values for the Mono, Bi and Tri Layer Topologies:

Assuming qQualMin = -16 dB And event2D for 3G-2G HHO = -14 dB

When UE is in Idle mode, we want it to select the most suitable cell:

Small hysteresis between cells

Fast reactivity

When UE is in Cell_FACH or Cell_PCH state, we prefer it to stay on its current

layer (in accordance to InterFreq or InterRAT HHO setting), even if increasing

the risk of call drop:

Larger hysteresis to prevent Ping-Pong in cell reselection (intra frequency)

Lower threshold to delay the triggering inter freq or inter system measurements



5 45

Exercise1: Mono-Layer Topology

Neighbouring Definition:

3G

2G

3G 3G

sSearchRatGsmNo 2G reselection until criteria

for HHO is reached

Objective

2dB

Connected ModeIdle Mode

Only Sib4 is used

qHyst2Prevent ping pong between cells on connected mode

Objective

2 dB


Objective is to prevent UE to go in 2G while staying in FACH-PCH State:



5 46

Exercise2: Bi-Layer Topology

3G (R99)

2G

3G (HSxPA)

3G (R99)

3G (HSxPA)

3G (R99)

3G (HSxPA)Only Sib4 is used

Same setting for SIB4 on both 3G layer

The objectives are to delay the inter-freq mobility and to prevent the UE to go on 2G while in FACH-PCH State

Give two values for SInterSearch when InterFreq or inter-Rat is preferred in the iMCTAsetting

No 2G reselection, first fallback to interfreq reselection

2 dBsSearchRatGsm

sInterSearch

qHyst2

Will depends on iMCTA Alarm priority setting

Prevent ping pong between cells on connected mode

Objective

6 dB

2 dBConnected ModeIdle Mode



5 47

Exercise2: Bi-Layer Topology [cont.]


2 dBsSearchRatGsm

sInterSearch

qHyst2

F1 F2 reselection allowed for load sharing


Objective

6 dB

2 dB


F1 & F2 settings

3G (HSDPA)

2G

3G (HSxPA)

3G (HSDPA)

3G (HSxPA)

3G (HSDPA)

3G (HSxPA)

Only Sib4 is used

The objectives are to delay the inter-freq mobility and to prevent the UE to go on 2G

while in FACH-PCH State



5 48

Exercise3: Tri-Layer Topology

3G (R99)

2G

3G (HSxPA)

3G (R99)

3G (HSxPA)

3G (R99)

3G (R99)

3G (HSxPA)

3G (R99)

3G (R99)

3G (HSxPA)

Because of load sharing between F1 & F3 (R99 cells), the strategy is to allow the UE to select the best cell (intra + inter-frequency F1+F3) in idle mode.

For connected mode (PCH / FACH), the strategy consists in keeping the UE on its current layer, except for R99: with load sharing purpose, it is accepted that the UE goes from F1 to F3 (and F3 to F1), but not on F2

F1

F2

F3



5 49

Exercise3: Tri-Layer Topology [cont.]


2 dBsSearchRatGsm

sInterSearch

qHyst2

F1 F3 reselection allowed for load sharing


Objective

6 dB

2 dB


F1 & F3 settings

No 2G reselection, first fallback to inter-freq reselection

2 dBsSearchRatGsm

sInterSearch

qHyst2

To delay the inter-freq mobility


Objective

6 dB

2 dBConnected ModeIdle Mode

F2 settings



5 50

Exercise3: Tri-Layer Topology [cont.]

Purpose of SIB 12 is to disadvantage F2 compared to F1 & F3 for Cell reselection

For which frequency (or frequencies) SIB12 will should be activated?

Disadvantage F2 compared to F1 & F3

0 dBqOffset2sn

F2

qOffset2sn

F1 & F3

Objective

0 dB




5 51

7 Cell Status and Reservation



5 52

7 Cell Status and Reservation

7.1 Cell Status and Reservation Process

barred

notReservedallowed notAllowed

only UE withAccess Classes 11 / 15

are accepted

reserved

try to selecta cell of anotherfrequency

if no other cell

all UE Access Classesare accepted

notReservedreserved

other UE

barredOrNot (FDDCell) = ..?

intraFreqCellReselectInd (FDDCell) = ..? cellReservedForOperatorUse (FDDCell) = ..?

cellReservationExtension (FDDCell) = ..?

try to reselectsame cell

wait tBarred (FDDCell)

notBarred

try to selectanother cell of the samefrequency



5 53

8 Location Registration



5 54

8 Location Registration

8.1 LAC/RAC/SAC

LAC 2

RAC 1

RAC 2

SAC 1

SAC 2

LAC 1

RNClocationAreaCode (FDDCell)routingAreaCode (FDDCell)serviceAreaCode (FDDCell)Core Network Domains

Sac (FDDCell->CBSResource)

Broadcast Domain



5 55

Module Summary

This lesson covered the following topics:

PLMN selection and associated parameters

Cell selection and associated parameters

Cell reselection and associated parameters



5 56

Self-assessment on the Objectives

Please be reminded to fill in the formSelf-Assessment on the Objectivesfor this module

The form can be found in the first partof this course documentation



5 57

End of ModuleModule 1

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3G-Mobility-Idle-Mode