最新整理GSM标准呼叫流程及相关计数器介绍.ppt

GSM 标准呼叫流程及相关计数器介绍标准呼叫流程及相关计数器介绍2GSM标准呼叫流程呼叫建立阶段共4 个阶段 呼叫，前2个用于位置更新>无线链路建立>“SDCCH通信阶段仅用于“电路”业务>TCH分配>“Alerting/connection“ 阶段每个阶段都可能会发生失败Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase3GSM标准呼叫流程无线链路建立－主叫（OC ）呼叫成功Originated Call: RLE success case>主要计数器•MC8C：统计业务区的MS发送的Channel Required消息•MC148：统计业务区的SDCCH 信道被激活的次数.•MC8B ：统计业务区的SDCCH 信道成功分配的次数•MC02：统计业务区的SDCCH 信道主叫主叫成功占用的次数>T7家族：•计数器: L1.18: TIME_LAPD_CONG•定义: 传输链路中的Lapd拥塞的时间呼叫建立失败的特殊事件：呼叫建立失败的特殊事件： 由于由于Lapd拥塞造成消息丢失拥塞造成消息丢失LapDRadio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase4GSM标准呼叫流程无线链路建立－TC 呼叫成功被叫：RLE 呼叫成功Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase5BSS性能管理统计分类B96GSM标准呼叫流程无线链路建立－主叫（OC ）呼叫成功计数器RLE > success MO splitMC02x=C02x MC02 =MC02A+MC02B+MC02C+…….+MC02G+MC02H+MC02iMC02A: LUMC02B: SMSMC02C: SSMC02D: LU follow-onMC02E: CRMC02F: unknownMC02G: IMSI DetachMC02H: EC or NCMC02i: LCS7GSM标准呼叫流程无线链路建立－SDCCH拥塞失败现象>无线链路建立 的主要失败原因Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX PhaseSDCCH Access FailureSDCCH CongestionSDCCH Radio FailureSDCCH BSS Problem8GSM标准呼叫流程无线链路建立－SDCCH拥塞RLE > SDCCH congestion>立即分配拒绝机制可以在 OMC-R 上禁止•paging不会触发该消息•如果禁止了,对于 MS主叫无回答>当拥塞的时候 ，MS 将会根据设置，间隔不同的时间设定来自动重复其请求－见下页Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase9GSM标准呼叫流程无线链路建立－SDCCH拥塞>发生拥塞后的两种情况：>1. 不发送Immediate Assignment Reject Command（ EN_IMM_ASS_REJ＝＝OFF或被叫或被叫MS）（1）MS等待T3120（MS计时器）超时后重发请求（2）T3120取值：–Phase1 MS：＝ 250+T-1（Slot）T随机取值（3－50） –Phase2 MS：＝ T＋S（Slot）T随机取值（3－50） S是根据信道配置和T值决定的>2.发送Immediate Assignment Reject Command（ EN_IMM_ASS_REJ＝＝ON）（对寻呼消息不响应）（1）MS在收到 Immediate Assignment Reject Command后等待T3122 再重发请求（2）T3122 =OMC参数－Wait_Indication•WI_OP－（0－255秒）:其他业务如LU，LCS•WI_OC－（0－255秒）：正常主叫业务•WI_EC－（0－255秒）：紧急呼叫业务•WI_CR－（0－255秒）：呼叫重建业务10GSM标准呼叫流程无线链路建立－SDCCH拥塞计数器RLE > SDCCH congestionMC04=C0411GSM标准呼叫流程无线链路建立－SDCCH拥塞RLE > SDCCH 拥塞主要的顺序> MS将会在放弃之前重试 “max_retrans +1 ” 次>对于大多数主叫业务，如果 “max_retrans+1” 失败, MS将根据业务类型决定下一步：•对LU, MS将会自动尝试一次新的 LU request，直到成功或达到最大LU次数•对呼叫业务, MS将不会自动重建呼叫，一般由用户或系统设置决定是否再次建立通话•以上行为MS都会尝试进行新的小区重选以提高接入成功率。

Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase12GSM标准呼叫流程无线链路建立－SDCCH拥塞起因RLE > SDCCH 拥塞主要原因>小区设计不当造成SDCCH拥塞•SDCCH信道资源太少 （呼叫过多）•位置区定义不当 （LU过多）>"Common Transport Effect"•对于尺寸小的小区很难避免>异常的SDCCH话务•伪信道请求•邻区被禁止接入（barred）Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase13GSM标准呼叫流程无线链路建立－SDCCH 拥塞解决方案RLE > SDCCH congestion动态动态SDCCH分配分配>SDCCH配置太多会导致TCH资源缺乏及浪费金钱 >SDCCH配置太少会导致SDCCH拥塞，TCH信道可能因为无法分配而被浪费>OMC-R可以支持动态SDCCH分配•静态SDCCH信道专用于SDCCH业务;•动态SDCCH信道既能用于SDCCH业务，也能用于TCH业务>利用这项特性，BSS可以根据SDCCH和TCH话务的动态变化灵活的分配SDCCH信道>.Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase14GSM标准呼叫流程无线链路建立－SDCCH 拥塞解决方案? RLE > SDCCH拥塞动态动态SDCCH分配分配CHANNEL REQUESTCHANNEL REQUIREDMSBTSBSC(RACH)If No free SDCCH, thenrun dynamic SDCCH/8 timeslot allocationalgorithm. If allocation is successful, thenactivate dynamic SDCCH sub-channel and serve requestIf allocation was unsuccessful, then reject SDCCH request (possiblyusing the Immediate Assignment Reject procedure).MC801a&bMC802a&bRadio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase15GSM标准呼叫流程无线链路建立－SDCCH 无线访问失败现象RLE > SDCCH无线失败现象SDCCH Access FailureSDCCH CongestionSDCCH Radio FailureSDCCH BSS ProblemRadio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase16GSM标准呼叫流程无线链路建立－SDCCH 无线访问失败现象RLE > SDCCH无线失败现象Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase17GSM标准呼叫流程无线链路建立－实际的无线问题RLE > SDCCH无线失败现象主要的起因 > 实际的无线问题>功率预算不平衡>覆盖不好>干扰>对于无线失败，MS会像SDCCH拥塞时一样进行重试Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase18GSM标准呼叫流程无线链路建立－Ghost RACHRLE > SDCCH 无线失败现象主要的起因 > “伪/克隆/假 ... RACH“>收到信道请求，但分配命令无回复 ，起因：•噪声误解码•相邻小区信道请求相同•相邻小区HO_ACCESS请求相同19GSM标准呼叫流程无线链路建立－BSS失败现象>无线链路建立 的主要失败原因Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX PhaseSDCCH Access FailureSDCCH CongestionSDCCH Radio FailureSDCCH BSS Problem20GSM标准呼叫流程无线链路建立－BSS problemRLE > BSS问题>无特定计数器Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase21GSM标准呼叫流程无线链路建立－计数器RLE counters Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX PhaseREQUESTCongestionATTEMPT无线访问失败现象呼叫成功BSS problemPreparation失败现象Execution失败现象GPRS 起因GSM/GPRS 非法起因GSM 合法 起因BSS problem22GSM标准呼叫流程SDCCH通信－主叫（OC ）呼叫成功呼叫成功 SDCCH通信 ：主叫（OC ）呼叫> 透明传输消息: 没有特定的计数器Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase23GSM标准呼叫流程SDCCH通信－TC 呼叫成功呼叫成功 SDCCH通信 ：TC 呼叫>透明传输消息: 没有特定的计数器Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase24GSM标准呼叫流程SDCCH通信－LU 呼叫成功呼叫成功 SDCCH通信 ：位置更新>透明传输消息: 没有特定的计数器Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase25GSM标准呼叫流程SDCCH通信－掉话SDCCH通信>SDCCH通信期间失去连接 = “SDCCH掉话“>3 个原因•无线问题•BSS问题•SDCCH 切换(切换失败没有返回旧信道Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase26GSM标准呼叫流程SDCCH通信－无线掉话SDCCH通信 >掉话 无线原因Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase27GSM标准呼叫流程SDCCH通信－BSS掉话SDCCH通信 >BSS 掉话>Connection lost due BSS problemRadio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase28GSM标准呼叫流程SDCCH通信－切换掉话SDCCH通信 >切换掉话>Connection lost during HandoverRadio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase29GSM标准呼叫流程SDCCH通信－计数器SDCCH phase counters TCH assignment phaseSDCCH dropSDCCH connectionNormal releaseDrop radioDrop BSSDrop HORadio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase30GSM标准呼叫流程TCH分配- 呼叫成功TCH分配- 呼叫成功 案例 >T3107: TCH 分配的保护定时器MC140aMC140bMC460aRadio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase31GSM标准呼叫流程TCH分配- TCH拥塞TCH分配- TCH拥塞（空口或Abis拥塞）>4 种拥塞原因  4 计数器: C612A, B, C, D, E 只要–不允许排队–队列已满–T11 过期–RTCH请求被从队列去掉(由于一个更高的优先级请求排队)Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase32GSM标准呼叫流程TCH分配- 无线失败现象TCH assignment >无线失败 >无线问题MC140aMC140bRadio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase33GSM标准呼叫流程TCH分配- BSS故障TCH assignment > BSS problem>BSS故障 (Abis, BTS/BSC HW or SW)MC140aMC140bNo specific counterRadio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase34GSM标准呼叫流程TCH分配- 计数器TCH分配计数器CongestionATTEMPTRadio access failureSUCCESSBSS problemPreparation FailureExecution FailureREQUESTBSS problemTCH AssignmentPreparationRequestMC140a CongestionMC812 BSS Pb MC140a-MC140b-MC812Execution Attempt MC140b Radio Access FailureMC746b BSS Pb MC140b-MC718-MC746bSuccessMC718Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase35GSM标准呼叫流程TCH通信阶段－呼叫成功TCH phase:>OC>TC>BSS透明数据传送，无计数器 ,期间可能会出现TCH掉话Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase36GSM标准呼叫流程TCH通信阶段－无线掉话TCH phase > 无线掉话>无线问题Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase37GSM标准呼叫流程TCH通信阶段－远程 TC掉话TCH phase > drop TC>远程 TC故障Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase38GSM标准呼叫流程TCH通信阶段－BSS内部掉话TCH phase > drop BSS internal>Other internal BSS problem (excluding TC)Radio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase39GSM标准呼叫流程TCH通信阶段－切换掉话TCH phase > drop HO>Handover failureRadio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase40GSM标准呼叫流程TCH通信阶段－预空（preemption）掉话TCH phase > drop preemption>TCH preemptedRadio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase41GSM标准呼叫流程TCH通信阶段－计数器典型呼叫失败: TCH phase counters Outgoing HO successCall dropTCH connectionNormal releaseCall drop radioCall drop BSSCall drop HOCall drop preemptionTCBSS internalNSS abnormal releaseRadio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase42GSM标准呼叫流程总结call stageA interfacecause fieldrelated problemradio linkestablishmentno message- SDCCH congestion- radio problem- Dummy rachSDCCH phaseClear Request- radio interface failure- radio interface failure- O&M intervention- radio problem- BSS system HW/SW pb- recovery/operatorTCH assignmentAssignment Failure - no radio resource avalaible- Radio Interface Failure- TCH congestion- Radio problemAlerting/connectioncall establishedClear Request- radio interface failure- radio interface message failure- equipment failure- O&M intervention- radio interface failure- preemption- radio problem- HO failure w/o reversion- Transcoder failure- operator action/recovery- BSS system HW/SW pb- preemptionRadio Link EstablishmentSDCCH PhaseTCH assignmentAlerting/CNX Phase。