【資料名稱(chēng)】：諾西2G3G互操作.ppt

【資料作者】：諾西

【資料日期】：2010-6-3

【資料語(yǔ)言】：中文

【資料格式】：PPT

【資料目錄和簡(jiǎn)介】：

GSM – WCDMA 互操作
3G/2G 互操作的實(shí)現(xiàn)方法
GSM系統(tǒng)升級(jí)
升級(jí)要求
In Idle Mode
Normally cell re-selection is done to cell having better coverage.
Both quality (CPICH Ec/No) and rxlevel (CPICH RSCP) should be good enough in the neighbour cell before cell re-selection can happen
Signal quality & level requirements are checked with S-criteria
Cell Ranking with R-criteria is done to select the best cell from all cells fulfilling S-criteria,
Cell selection: S準(zhǔn)則
Cell selection: S準(zhǔn)則
Cell selection: S準(zhǔn)則
Cell Re-selection: R準(zhǔn)則
Cell Reselection 3G -> 2G Procedure
Cell Re-selection: R準(zhǔn)則
Serving cell parameters Sintrasearch, Sintersearch and SsearchRAT (Intra-, Inter-frequency, Inter-RAT Measurement Thresholds respectively) are compared with Squal (CPICH Ec/No - Qqualmin) in S-criteria for cell re-selection.
UE will measure neighbour cells depending on how the measurement threshold parameters are set & sent (if parameters are not sent, UE shall measure all cells)
1 None (Squal > Sintrasearch ) – UE need not perform intra-frequency measurements.
2 WCDMA intra-frequency (Sintersearch < Squal  Sintrasearch)
3 WCDMA intra- and inter- frequency, no inter-RAT cells (SsearchRAT < Squal  Sintersearch)
4 WCDMA intra- and inter-frequency and inter-RAT cells (Squal  SsearchRAT )
WCDMA to WCDMA Cell Re-selection
WCDMA to GSM Cell Re-selection NSN Strategy: reselect to GSM early
Idle Mode Cell Reselection Parameter
WCEL: Qhyst1 (Qhyst2) Qhyst1 is used for TDD and GSM cells, and for FDD cells when cell selection and re-selection quality measure is set to CPICH RSCP (CPICH Ec/No) (Qhyst1s/ Qhyst2s). This parameter is part of SIB 3. [0 ... 40] dB, step 2 dB, default: 4 dB.
HOPS: AdjsQoffset1 (AdjsQoffset2) This parameter is used in the cell re-selection and ranking between WCDMA cells. The value of this parameter is subtracted from the measured CPICH RSCP (CPICH Ec/No) of the intra-frequency neighbour cell before the UE compares the quality measure with the cell re-selection/ranking criteria. [-50 ... 50] dB, default: 0 dB. HOPS: AdjsQoffset1 (AdjsQoffset2), HOPG: AdjgQoffset1, (AdjgQoffset2)
WCELL: Treselection The UE triggers the reselection of a new cell if the cell reselection criteria are fulfilled during the time interval Treselection. This parameter is part of SIB 3. [0 ... 31] seconds, default: 0 seconds. 現(xiàn)網(wǎng)設(shè)為2s，重選速度變慢，但可能減少乒乓重選
Crucial Cell (Re-)selection Parameters
Minimum required CPICH RSCP/RXLEV of the neighbour cell for cell re-selection
GSMncellQrxlevMin (RXLEV, -110..-47 dBm, step 2, default -105 dBm)
InterFreqNcellQrxlevMin, IntraFreqNcellQrxlevMin (CPICH RSCP, -115 ... -25 dBm, step 2 dBm, default -115 dBm)
InterFreqNcellQqualMin, IntraFreqNcellQqualMin (Ec/No, -20 ... 0 dB, step 1 dB, default -20 dB)
Offset values (CPICH RSCP/RXLEV) to be subtracted from neighbour cell before quality comparison (re-selection & ranking)
InterFreqNcellQoffset1, IntraFreqNcellQoffset1, GSMncellQoffset1
InterFreqNcellQoffset2, IntraFreqNcellQoffset2
Range -50 ... 50 dB, step 1 dB, default 0 dB
Hysteresis values of serving cell used in ranking R- criteria
Qhyst1 (for GSM cells RSSI, WCDMA CPICH RSCP)
Qhyst2 (for WCDMA cells CPICH Ec/No)
Range 0 ... 40 dB, step 2 dB, default 0 dB

In Connected Mode
Triggers for Connected Mode ISHO shall be based on Coverage Reason:系統(tǒng)間切換只能根據(jù)CPICH的RSCP值來(lái)判定
CPICH RSCP
Not enabled: CPICH Ec/NO, UE Tx Power, UL Quality, DL Quality
Rational for ISHO Trigger using CPICH RSCP only:
To avoid unnecessary ping-pong ISHO in areas of slight pilot pollution within Urban city area, where CPICH Ec/No values may hit the planned threshold to trigger ISHO unnecessarily.


系統(tǒng)間切換信令流程
UE發(fā)送切換觸發(fā)消息到RNC后，RNC發(fā)送RRC消息“Measurement Control”到 UE，指導(dǎo)UE對(duì)目標(biāo)GSM小區(qū)進(jìn)行測(cè)量，并周期性發(fā)回測(cè)量報(bào)告




收到UE上報(bào)的測(cè)量報(bào)告后，RNC應(yīng)用“滑動(dòng)平均窗口”對(duì)所有測(cè)量值進(jìn)行對(duì)比分析，以決定 IS-HO

RNC informs UE of CM pattern and 2G neighbour list in RRC: Measurement Control message
3GPP states that the UE must be capable of recording a minimum number of GSM RSSI measurement samples per transmission gap
GSM RSSI measurements are made without acquiring GSM synchronisation
UE reports on strongest 6 GSM neighbours at periodic interval defined by GSMMeasRepInterval
RNC applies a sliding averaging window to the measurements provided by the UE
RNC instructs UE to perform BSIC verification (AMR=always, PS=as required) using new CM pattern
BSIC verification needs synchronisation to GSM frame
系統(tǒng)間測(cè)量與壓縮模式
壓縮模式：通過(guò)降低擴(kuò)頻因子、打孔方式或者PS Scheduling，把信息壓縮在較短幀長(zhǎng)內(nèi)發(fā)送,以騰出時(shí)間進(jìn)行系統(tǒng)間(頻率間)測(cè)量。

影響:相比正常情況，壓縮模式需要更多的功率，容易對(duì)覆蓋造成影響。
在壓縮模式下，功率控制不再工作,容易造成更多干擾,影響網(wǎng)絡(luò)容量。
壓縮模式對(duì)容量的影響
壓縮模式對(duì)覆蓋影響
ISHO 3G -> 2G - AMR Signaling Flow
BSIC verification always performed for AMR calls – no interrupt in voice call
ISHO 3G -> 2G - PS Signaling Flow

2G to 3G 互操作

2G/3G互操作策略需要考慮的問(wèn)題
2G-3G互操作場(chǎng)景示意
3G網(wǎng)絡(luò)發(fā)展不同階段對(duì)功能和互操作的要求
3G網(wǎng)絡(luò)部署初期的互操作示意
WCDMA發(fā)展現(xiàn)階段2G3G策略 總結(jié)

Cell Reselection, WCDMA -> GSM, Parameters
ISHO WCDMA -> GSM, Parameters
ISHO WCDMA -> GSM, Parameters

3G/2G互操作KPI-CS域
3G/2G互操作KPI-PS域
3G/2G互操作KPI-PS域
3G/2G互操作優(yōu)化
謝　謝