huawei

3G2G HandOver and Roaming

Brief Brief

In Idle Mode , UE use cell reselection to enter GSM Network

Connect Mode, UE use HandOver to enter GSM Network.

Cell Selection Cell Selection

PLMN Selection

1) when ue is power on , it scans RF and read MIB

to define whether this cell’s PLMN is what it wants.

2) PLMN has order list .

Auto Selection

i) RPLMN

ii) Home PLMN

iii) User or Operator controlled PLMN selector with Access

Technology

Manual Selection

Read SIB3 , Evaluate S Criteria IF matchs S Criteria , Camped on the cell ,then LA/RA update.

Else

read SIB11 finds neighbor cells ， Evaluate S Criteria for neighbor cells

if matched ,

camped

else

scan other cells or in PLMN selection.

end

camped on any cell .

Cell ReselectionCell Reselection

All Neighbor Cell evaluate S criteria .

In S>0 cells , Compute R value.

Select Rmax Cell .

S & R CriteriaS & R Criteria

Squal = Qqualmeas - Qqualmin

Srxlev = Qrxlevmeas - Qrxlevmin - Pcompensation

Squal > 0

Srxlev > 0

Rs = Qmap,s + Qhysts

Rn = Qmap,n - Qoffsets,n - TOn * (1 - Ln)

Cell Selection &Reseletion Parameters(1)Cell Selection &Reseletion Parameters(1)

Qqualmin Value range: -24 -- 0 (dB)Content:  Minimum required quality level corresponding to the CPICH Ec/No. UE can  camp

on the cell only when the CPICH Ec/No measured is larger than the value of this parameter.

Recommended value: -18(dB).

Qrxlevmin Value range: -58 -- -13. (dBm)Physical value range: -115 -- -25; step: 2 (-58: -115; -57:-113; ..., -13:25). Content: Minimum required RX level corresponding to the CPICH RSCP. UE can camp on

the cell only when the measured CPICH RSCP is larger than the value of this parameter.. Recommended value: -58.

Qqualmeas Measured cell quality value. The quality of the received signal expressed in CPICH Ec/N0 (dB) for FDD cells. Not applicable for TDD cells or GSM cells.

Qrxlevmeas Measured cell RX level value. This is received signal, CPICH RSCP for FDD cells (dBm), P-CCPCH RSCP for TDD cells (dBm) and RXLEV for GSM cells (dBm).

Pcompensation Max(UE_TXPWR_MAX_RACH – P_MAX, 0) (dB)

Pmax Value range: -50 -- 33 (dBm) Content: Allowed maximum power transmitted on RACH in the cell. It is related to network

planning. Recommended value: 24.

Cell Selection &Reseletion Parameters(2)Cell Selection &Reseletion Parameters(2)Treselectiontime

Value range: 0~31 Physical unit: second.

Content: If the signal quality of a neighbor  cell is better than the serving cell during the

specified time of this parameter, the UE will reselect the neighbor cell. It is used to avoid

ping-pong reselection of UE between different cells. Note: 0 does not refer to 0 second but

corresponds to the default value defined in the protocol.

Recommended value: 0.

Ssearch.RAT Value range: -16~10 Physical value range: -32 ~ 20; step: 2. Physical unit: dB. Content: Threshold for inter-RAT cell reselection. When the quality (CPICH Ec/No measured by UE) of the serving cell is lower than the threshold plus the minimum required quality  ( Qqualmin) of the cell, the inter-RAT cell reselection procedure will be started. It's mandatory When the value of parameter SsearchratInd is TRUE. Recommended value: 2.

Qhyst1s Value range: 0-20 Physical value range: 0 – 40(dB); step: 2. Content: Hysteresis  value for serving FDD cells in case the quality measure for cell selection and re-selection is set to CPICH RSCP. It changes with the slow-fading feature of the area where the cell is located. The bigger the slow-fading variance is, the bigger this value of the parameter. Recommended value: 2.

Qhyst2s Value range: 0 - 20 Physical value range: 0 – 40 (dB); step: 2.Content: Hysteresis  value for serving FDD cells in case the quality measure for cell selection and re-selection is set to CPICH Ec/No. It changes with the slow-fading feature of the area where the cell is located. The bigger the slow-fading variance is, the bigger this value of this parameter. Recommended value: 1.

CELL Selection & Reselection MML COMMANDCELL Selection & Reselection MML COMMAND

Cell Selection & Reselection Command

1) MOD CELLSELRESEL

2) MOD INTERRATNCELL

3) MOD CELLMEAS

HandOver -CS_3G->2G （ 1 ）HandOver -CS_3G->2G （ 1 ）UE

1. RRC Connect Req

15. RAB Assign Req

NODEB RNC 3G MSC BSS2G MSC

2. RRC Setup Complete

3. Measure Control (measure ID 0x1 )

4. Measure Control (measure ID 0x2 )

5.Initial UE message(service request)

6.DL DT (Authentication Request)

7.UL DT (Authentication Response)8.Common ID

9. Security Mode Command10. Security Mode Command

11. Security Mode CMP12. Security Mode CMP

13. UL DT(Setup)14. DL DT(Call proceeding)

17.RL Recfg Ready

21 RAB Assign Resp20 RB Setup Cmp

19 RB Setup

16.RL Recfg Prep

18.RL Recfg Commit

22. DL DT( Alerting )

23. DL DT( Connect)

24. UL DT(Connect Ack)

26.RL Recfg Prep26.RL Recfg Prep

28 PhyCh Reconfig28 PhyCh Reconfig29.RL Recfg Comit29.RL Recfg Comit

27.RL Recfg Ready27.RL Recfg Ready

30 PhyCh Reconfig CMP30 PhyCh Reconfig CMP31 Meaure Control(ID3 )

32Measure Report 33 Relocation Required

34 Relocation Command35. HandoverFromUtranCommand

44 Iu Release Req

46 RL Del Resp45 RL Del Req

47 Iu Release Complete

25 Measure Report(2D)

HandOver-CS_3G->2G （ 2 ）HandOver-CS_3G->2G （ 2 ）UE NODEB RNC 3G MSC BSS2G MSC

35. BSSMAP Handover Request

37. MAP/E Prepare Handover Response

38. Relocation Commond

39. HandoverFromUtranCommand

41. Handover Complete

33 Relocation Required

44 Iu Release Command

46 RL Del Resp

45 RL Del Req

47 Iu Release Complete

34. MAP/E Prepare Handover

36. BSSMAP Handover Request Ack

40. BSSMAP Handover Detect

42. BSSMAP Handover Complete43. MAP/E Send End Signal

Required

48. MAP/E Send End Signal response

Measurement Control ID2-CS_3G->2G（ 3 ）

Measurement Control ID2-CS_3G->2G（ 3 ）

Measurement Control ID3-CS_3G->2G（ 4 ）

Measurement Control ID3-CS_3G->2G（ 4 ）

Measurement Report ID3-CS_3G->2G （ 5 ） Measurement Report ID3-CS_3G->2G （ 5 ）

HandOver&Relocation-CS_3G->2G （ 5 ）HandOver&Relocation-CS_3G->2G （ 5 ）

Some Record Message-CS_3G->2G （ 6 ）Some Record Message-CS_3G->2G （ 6 ）

IU_3ghandoverto2g_sec.tmf Iub_3ghandoverto2g_sec.tmfuU_3ghandoverto2g_sec.tmf

A_handover.GMTuser_handover.UIT

HandOver -CS_2G->3GHandOver -CS_2G->3G

UE NODEB RNC 3G MSC BSS2G MSC

7. MAP/E Prepare Handover Response

6. Relocation Request Ack

12. Relocation Complete

10 RL Restore Ind

3 Relocation Request

1.BSSMAP Handover Request

2. MAP/E Prepare Handover

4. Radio Link Setup

5. Radio Link Setup RSP

8. MAP/E Handover Command

9. Handover to UTRAN Command

11. Handover to UTRAN Complete

16. MAP/E Send End signal response

13. MAP/E Send End Signal request 14.BSSMAP Clear Command

15.BSSMAP Clear Complete UTRAN MobilityInfo

UE Capability enquiry

UTRAN MobilityInfo Confirm

UE Capability Info

UE Capability Info Confirm

UE NODEB RNC 3G SGSN 2G SGSN

3.SGSN Context Request

1 . Cell Change Order from UTRAN

6. SGSN Context Ack

2 Route Area Update Requeset

9 Update PDP Context Request

15 Iu Release Complete

7 SRNS Data Forward Command

10 Update GPRS location

11. Cancel Location

9.Update PDP Context Response

11. Update GPRS location Ack

InterSystem Change decision

HandOver-PS_3G->2.5GHandOver-PS_3G->2.5G

. Measure Report

GGSN HLR

4.SRNS Context Request

4.SRNS Context Responset

5.SGSN Context Responset

8 Forward Packet 8 Forward Packet

12. Cancel Location

12 Iu Release Command13 14 RL release

12 Route Area Update Accept

Message-PS_3G->2.5GMessage-PS_3G->2.5G

iu.tmfiub.tmf

single u.tmfuu.tmf

RAT HandOver MML COMMAND Add GSM cell （ 1 ）

RAT HandOver MML COMMAND Add GSM cell （ 1 ）

MCC 移动国家号 CELL ID GSM 小区 ID

MNC 移动网络号 BSIC 基站识别码

LAC 位置区号 BCCH ARFCN 绝对频率号

配置命令 1 ： ADD GSMCELL: MCC="460", MNC="07", LAC="0001", CID="0011", NCC=1, BCC=3, BCCHARFCN=19, ANDIND=DCS1800_BAND_USED,RATCELLTYPE=GSM;

GSM cell’s Data （ 2 ）GSM cell’s Data （ 2 ）CGI : Cell Global Identification

MCC | MNC | LAC | CI |

Location Area Identification

Cell Global Identification

• Identify unique GSM

BSIC: Base Station Identify Code , 由 NCC 和 BCC 构成；

| NCC | BCC | 3 bits 3 bits

• MS can use it to distinguish cells with the same BCCH frequence ；• Network can distinguish cells when received report ；

GSM cell’s Data （ 3 ）GSM cell’s Data （ 3 ）ARFCN : Absolute Radio Frequency Channel Number

P-GSM 900 Fl(n)=890+0.2*n 1<=n<=124 Fu(n)=Fl(n)+45

E-GSM 900 Fl(n)=890+0.2*n 0<=n<=124 Fu(n)=Fl(n)+45

Fl(n)=890+0.2*(n-1024) 975<=n<=1023

DCS 1800 Fl(n)=1710.2+0.2*(n-

512)

512<=n<=885 Fu(n)=Fl(n)+95

Fl (n) : the frequency value of the carrier ARFCN n in the lower band, Fu(n) : the corresponding frequency value in the upper band

RAT HandOver MML COMMAND （ 4 ）

RAT HandOver MML COMMAND （ 4 ）

SET INTERFREQHO (Object RNC )

MOD CELLINTERFREQHO (Object Cell)

SET INTERRATHO (Object RNC)

MOD CELLINTERRATHO (Object Cell)

RAT HandOver ParametersRAT HandOver Parameters

Tuse2d ( Pcpich Rscp dBm) : -95dBm

CIO : 5dB

Inter-RAT handover trigger time : 1s

GsmRSSI Threshold : -95 dBm

ReferenceReference

3GPP TS 25.304: "UE Procedures in Idle Mode and Procedures for Cell Reselection in

Connected Mode".

3GPP TS 25.331: "Radio Resource Control (RRC); protocol specification".

3GPP TS 23.060: "General Packet Radio Service (GPRS); Service description; Stage

2".

3GPP TS 03.03: "Digital cellular telecommunications system (Phase 2+); Numbering,

addressing and identification"

3GPP TS 05.05: "Digital cellular telecommunications system (Phase 2+); Radio

transmission and reception".

系统间互操作白皮书终稿 _ 注释 Nokia 3G and GSM Roaming and Handover

NOKIA 测试指导书 WCDMA 与 GSM 系统间漫游及其切换原理分析报告 关于 WCDMA 、 GSM 并网运行的方案考虑 _ 移机不换号

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