卡特-gsm呼叫流程-附多媒体讲座ppt课件

1、GSM呼叫流程目的和内容目的引见GSM正常的呼叫流程空中接口、A-bis接口和A接口引见部分常见的异常中断的流程内容GSM网络协议引见GSM逻辑信道引见无线链路建立流程Radio and Link Establishment ProcedureTCH正常分配流程Normal Assignment Procedure 主叫流程Originating Call被叫流程Terminating Call位置更新流程Location Updating切换流程Handover Procedure呼叫释放流程Call Release Procedure信道释放流程Channel Release Proced

2、ureGSM协议层数无线网络优化主要关怀第三层的信令无线网络优化主要关怀DTAP、RSL的信令无线网络优化主要关怀DTAP、BSSMAP和部分SCCP的信令DTAPRSLOMLGSM网络协议Layer 3引见RR : 无线资源管理Radio Resource Management由MS、BTS和BSC控制功能举例Paging管理Paging Management加密管理Ciphered Mode Management频点分配Frequency Redefinition信道分配Dedicated Channel Assignment切换Handover Management 丈量和功率控制Mea

3、sures and Power ControlMM : 挪动性管理Mobility Management由MS和MSC / VLR控制功能举例鉴权和身份识别Authentication / Identification Procedures位置更新Location UpdatingIMSI Attach / DetachGSM网络协议CC : 呼叫控制Call Control由MS和MSC控制功能举例呼叫处置和路由Call processing and routing双音多频DTMF Facilities短音讯效力Short Message Service附加效力Supplementary S

4、erviceGSM网络协议呼叫流程中常用的逻辑信道PCH寻呼信道Paging ChannelRACH随机接入信道Random Access ChannelAGCH接入认可信道Access Grant ChannelSDCCH独立公用控制信道Stand-alone Dedicated Control ChannelSACCH慢联络控制信道Slow Associated ChannelTCH话务信道Traffic ChannelFACCH快联络控制信道Fast Associated Control ChannelGSM呼叫流程中常用的逻辑信道PCHRACHAGCHSDCCH + SACCHTCH/

5、FACCH + SACCH定义手机与网络间建立一个无线链路，用于信令传送包括以下四个步骤Paging过程Paging Procedure仅用于被叫流程中随机接入过程Random Access Procedure立刻分配过程Immediate Assignment ProcedureSCCP联接建立过程SCCP Connection Establishment Procedure 当手机需求与网络发生联络时，必需求先建立无线链路和A接口的信令衔接无线链路建立流程MSBTSBSCMSCChannel RequestChannel RequiredChannel ActivationSDChanne

6、l Act Ack SDImmediate AssignmentCommandUI Imm Assignment / Imm Ass ExtST9103ET9103ST3126ET3126ST3101SABM L3 InfoEst Ind L3 InfoSCCP Con Rqrd L3SCCP Conn ConfirmET3101ST9105ET9105UA L3 InfoRACHEst Cause，Rnd NbrEst Cause，Rnd Nbr，TARACH_TA_FilteringTA，BS/MS_TxPwr -Max，ChannTimer；S - Start；E - EndEntity

7、信令音讯空中接口Abis接口A接口Rnd Nbr，TDMA Frame Nbr，Chan ，TAAGCH同时对两个MS分配SDCCHSDCCHBSC开场对MS发出的上行DTAP音讯排队如CM Serv Abort音讯。假设收到MS发出的Classmark Change音讯，BSC会在SCCP衔接完成后发Classmark Update音讯给交换机如CM Serv Req，Pag Res，Loc Update Req等Set Asynchronous Balance Mode。在任何新信道登陆时均会有SABM过程Unnumbered Ack无线链路建立流程无线链路建立流程AbisAbis信令Ch

8、annel Required无线链路建立流程AbisChannel Activation无线链路建立流程AbisImmediately Assignment无线链路建立流程异常情况SDCCH拥塞假设BSC在收到Channel Required时，相应小区没有空闲的SDCCH，BSC将会假设小区参数En_Imm_Ass_Rej=“True，那么发Immediately Assignment Reject否那么忽略Channel Required音讯T9103超时BSC发RF Channel Release音讯到BTSBSC收到Channel Activation NAck音讯BSC内部释放BTS

9、的相应无线信道 (没有任何音讯在Abis接口上传送) T3101超时Layer 3无法建立 BSC发RF Channel Release到BTST9105超时BSC经过呼叫释放过程 Call Release Procedure释放原先建立的SDCCH衔接在A接口，BSC向MSC发SCCP释放恳求 在RF部分，BSC向手机和BTS发信道释放音讯 仅在BSC内部资源表中释放，在Abis上没有信令传送BSC收到Establish Indication音讯，但音讯中不含Layer 3 InformationBSC向手机和BTS发信道释放音讯Abis上的其它异常中断音讯的处置BSC收到Error Ind

10、icationCause为 : “T200 Expiry : 监视SABM和UA过程“Unsolicited DM Response (发生在Disconnect过程中“Sequence Error释放：A接口上，BSC发Clear Request “Radio Interface Failure到交换机BSC向手机和BTS发信道释放音讯BSC收到Connection Failure indication (Cause : Radio Link Failure)在A接口上，BSC发Clear Request “Radio Interface Failure到交换机BSC向BTS发RF Chan

11、nel Release音讯BSC收到Release Indication当收到手机发出的DISC音讯A接口上，BSC发Clear Request “Radio Interface Failure到交换机BSC向手机和BTS发信道释放音讯无线链路建立流程异常情况MSBTSBSCMSCAuthentication ReqCiphering Mode CmdAuthentication ReqAuthentication ReqAuthentication RespAuthentication RespAuthentication RespEncryption CommandCiphering Mo

12、de CmdCiphering Mode CmpCiphering Mode CmpCiphering Mode CmpTMSI Realloc CmdTMSI Realloc CmdTMSI Realloc CmdTMSI Realloc CmpTMSI Realloc CmpTMSI Realloc CmpAuthenticationCipheringTMSI ReallocST3260ET3260*Authentication Reject*IdentificationIdentification RequestST3270ET3270Identification RequestIden

13、tification RequestIdentification ResponseIdentification RespIdentification ResponseST3250ET3250RANDSRESRAND与Ki经过A3算法得到SRES；经过A8算法得到Kc比较SRESIMSI选择加密算法Permitted Alg，Kc预备解密接纳Alg，KcAlgA5算法开场加密发射和解密接纳如正确解密接纳，那么下条音讯加密发射已加密的音讯TMSIVLR从HLR处得到RAND/SRES/Kc鉴权、身份识别、加密、TMSI重新分配过程鉴权、身份识别、加密、TMSI重新分配过程A口信令Authentic

14、ation Request鉴权、身份识别、加密、TMSI重新分配过程A口信令Authentication Response鉴权、身份识别、加密、TMSI重新分配过程A口信令Identification Response鉴权过程中的异常情况鉴权失败假设鉴权过程中运用TMSI，网络将启动身份识别过程。假设手机送上来的IMSI与VLR中TMSI所对应的IMSI不一致，那么重新进展鉴权假设鉴权过程中曾经运用IMSI，那么网络发Authentication Reject音讯。这个SIM将被以为是无权的T3260超时第一次超时，网络将重发鉴权恳求；第二次超时，网络将释放该MM衔接身份识别过程中的异常情况T

15、3270超时第一次超时，网络将重发身份识别恳求；第二次超时，网络将释放该MM衔接TMSI重新分配过程中的异常情况T3250超时第一次超时，网络将重发TMSI重新分配恳求；第二次超时，网络将释放该MM衔接鉴权、身份识别、加密、TMSI重新分配过程异常情况定义分配TCH的过程特殊情况排队Queuing直接重试Directed RetryTCH分配过程MSBTSBSCMSCChannel Activation TCHSABM (FACCH)Channel Activation Ack.Assignment CommandAssignment CommandAssignment RequestPhys

16、ical Context RequestPhysical Context ConfirmEstablish IndicationUAAssignment CompleteAssignment CompleteAssignment CmpRF Channel Release (SD)RF Channel Release Ack.STrr1ETrr1ST9108ET9108ST9103ET9103ST3107ET3107Chn Type，Priority，CIC，DL DTX，Queuing FlagTA，MS/BS_TxPwrSDCCHTA，MS/BS_TxPwrMA，TS，HSN，MAIO，M

17、S_TxPwr占用TCH时，如需传送信令，那么经过Stealing Flag将TCH转换成FACCH普通情况下，在RF信道释放前都有Physical Context Req过程TCH分配过程TCH分配过程A口Assignment RequestEFRQueuingTCH分配过程AbisAssignment CommandFrequency EncodingBitmap 0MSBTSBSCMSCSABM (FACCH)Channel ActivationHO CMDAssignment RequestPhysical Con ReqChan. Act. Ack.HO DetectionUAPhy

18、s. InfoAssignment CmpST11ST3103Queuing IndicationET11At this time, a TCH become freeTCH拥塞和排队Assignment RequestST11Queuing IndicationET11A Handover alarm is raised. A target BTS is selectedHO CMDHO AccessST9103ET9103TTSTTEstablish IndicationTTHO CMPTHO CMPST3124ET3124ET3103直接重试假设Queuing Ind=True或Queu

19、ing_Anyway=True。当Queuing _Anyway时T11_Forced取代T11TCH分配过程排队和直接重试TCH拥塞情况不允许排队或队列已满在A接口BSC发Assignment Failure No Radio Resource Available呼叫进入队列，但T11时间内没有TCH空出在A接口BSC发Clear Request No Radio Resource Available呼叫被优先级更高的呼叫挤出队列在A接口BSC发Assignment Failure No Radio Resource AvailableT9108超时 : BTS对physical conte

20、xt request没有呼应之后的Channel Activation音讯中将不带TA和手机及BTS的发射功率信息T9103超时 : Channel Activation没有回应A接口上BSC发Assignment Failure Radio Interface FailureBSC向BTS发RF Channel Release音讯TCH分配过程异常情况BSC收到Channel Activation Negative Acknowledge音讯Channel Activation Negative Acknowledge有以下几种缘由 :Channel Already Activated (C

21、AA): BSC向手机和BTS发信道释放音讯Radio Resource Not Available (RRNA) - Protocol error (PE) : BSC内部释放Requested transcoding rate not supported (RTRNS) : BSC内部释放Encryption algorithm not implemented (EANI) : BSC内部释放O&M Intervention (OI) : BSC内部释放在A接口上发Assignment Failure音讯对于收到Chnav Neg Ack缘由为EANI的情况，Assignment Fail

22、ure的cause为Ciphering Algorithm not supported其它情况， Assignment Failure的cause为Radio Interface FailureTCH分配过程异常情况在原来的信道上如SDCCH信道收到Assignment Failure音讯 手机收到Assignment Command后，在新信道上发SABM音讯，BTS收到后向手机发UA音讯。但能够由于空中接口缘由，手机没有收到UA音讯。手机尝试N200次均未胜利。手机将会回到原来的信道。并发Assignment Failure音讯BSC收到该音讯后在A接口发Assignment Failur

23、e Reversion to Old ChannelBSC向BTS发RF Channel Release音讯，释放新信道Assignment Command的内容有误手机发现Assignment Command音讯中内容有误，手机发Assignment Failure音讯到BSCBSC收到该音讯后在A接口发Assignment Failure Reversion to Old ChannelBSC向BTS发RF Channel Release音讯，释放新信道T3107超时BSC在A接口发Assignment Failure “Radio Interface Message Failure，并开

24、场T9110计时BSC向BTS发RF Channel Release音讯，释放新老信道MSC向BSC发Clear Command音讯呼叫释放，并停顿T9110普通情况下，交换机收到该音讯后发DISCtemp failTCH分配过程异常情况直接重试中的异常情况没有Candidate cellBSC在A接口发Assignment Failure “No Radio Resource AvailableChannel Activation过程中T9103超时 BSC在A接口发Assignment Failure “Radio Interface FailureBSC向BTS发RF Channel R

25、elease音讯BSC收到Channel Activation Negative Acknowledge音讯Channel Activation Negative Acknowledge有以下几种缘由 :Channel Already Activated (CAA): BSC向手机和BTS发信道释放音讯Radio Resource Not Available (RRNA) - Protocol error (PE) : BSC内部释放Requested transcoding rate not supported (RTRNS) : BSC内部释放Encryption algorithm no

26、t implemented (EANI) : BSC内部释放O&M Intervention (OI) : BSC内部释放在A接口上发Assignment Failure音讯对于收到Chnav Neg Ack缘由为EANI的情况，Assignment Failure的cause为Ciphering Algorithm not supported其它情况， Assignment Failure的cause为Radio Interface FailureTCH分配过程异常情况T3103超时 : 没有收到HO Failure或HO Complete音讯BSC在A接口发Assignment Failu

27、re “Radio Interface message FailureBSC向手机和BTS发信道释放音讯，释放新老信道收到手机发来的HO Failure音讯BSC在A接口发Assignment Failure “Reversion to Old Channel音讯BSC向BTS发RF Channel Release音讯，释放新信道Abis上的其它异常中断音讯的处置BSC收到Connection Failure Indicaiton音讯Cause为 : “Radio Interface Failure : 无线链路超时引起的释放释放：A接口上，BSC发Clear Request “Radio I

28、nterface Failure到交换机BSC向BTS发RF Channel Release音讯BSC收到Error Report音讯BSC收到Error Indication音讯BSC收到Release Indication音讯A中继信道拥塞或不可用情况TCH分配过程异常情况主叫过程非OACSU情况MSBTSBSCMSCCall ProceedingESTIN (CM_Serv_Req)RR Connection EstablishmentRR Connection EstablishmentRR Connection EstablishmentAuthentication Procedur

29、eAuthentication ProcedureAuthentication ProcedureCiphering ProcedureCiphering ProcedureCiphering ProcedureTMSI Realloc ProcedureTMSI Realloc ProcedureTMSI Realloc ProcedureSETUPSETUPSETUPCall ProceedingCall ProceedingAssignment ProcedureAssignment ProcedureAssignment ProcedureAlertingAlertingAlertin

30、gConnectConnectConnectConnect Ack.Connect Ack.Connect Ack.SpeechCM_Serv_ReqOff Air Call Setupcalled party nbr先建立TCH，再接通B侧信道。Alerting在TCH上发送CM Serv Type，Mobile ID，Classmark2，Priority，SDCCHTCH主叫过程 A口CM Service Request主叫：MOC est/pkt mode con estab短信：Short message service附加效力：Suppl service activationCLA

31、SSMARKCLASSMARK包含以下信息MS Revision Level 手机的修正版本MS Ciphering Capability 手机支持的加密算法MS Frequency Capability 手机支持的频段MS RF Power Capability in Each Band 手机在各频段支持的发射功率主叫过程 A口Setup主叫过程 A口被叫号码MSBTSBSCMSCCall ProceedingESTIN (CM_Serv_Req)RR Connection EstablishmentRR Connection EstablishmentRR Connection Estab

32、lishmentAuthentication ProcedureAuthentication ProcedureAuthentication ProcedureCiphering ProcedureCiphering ProcedureCiphering ProcedureTMSI Realloc ProcedureTMSI Realloc ProcedureTMSI Realloc ProcedureSETUPSETUPSETUPCall ProceedingCall ProceedingAssignment ProcedureAssignment ProcedureAssignment P

33、rocedureAlertingAlertingAlertingConnectConnectConnectConnect Ack.Connect Ack.Connect Ack.SpeechCM_Serv_ReqSDCCHTCH先接通B侧信道，再建立TCH 。Alerting在SDCCH上发送主叫过程OACSU情况MSBTSBSCMSCCall ConfirmedESTIN (Paging Resp)RR Connection EstablishmentRR Connection EstablishmentRR Connection EstablishmentAuthentication Pr

34、ocedureAuthentication ProcedureAuthentication ProcedureCiphering ProcedureCiphering ProcedureCiphering ProcedureTMSI Realloc ProcedureTMSI Realloc ProcedureTMSI Realloc ProcedureSETUPSETUPSETUPCall ConfirmedCall ConfirmedAssignment ProcedureAssignment ProcedureAssignment ProcedureAlertingAlertingAle

35、rtingConnectConnectConnectConnect Ack.Connect Ack.Connect Ack.SpeechPaging ResponsePagingPaging CommandPaging RequestST3113ET3113Paging Group的个数N：由BS_AG_BLKS_RES和BS_PA_MFRMS决议;MS的Paging Group = (IMSI mod 1000) mod N;MS只监听本人对应的Paging Group的Paging Req音讯MS IDTMSI/IMSI，Cell IDLAC/LAC+CIMS IDTMSI/IMSI，Pa

36、ging GroupMS IDTMSI/IMSI最多可同时发4个TMSIMobile ID，Classmark2，Priority，calling party nbr被叫过程Paging被叫过程 A口IMSI号码，BSC用来计算Paging GroupTMSI号码，空中接口Paging时用，比较经济LAC PagingA口信令被叫过程 A口Setup被叫过程 A口主叫号码T3113超时假设T3113超时，Paging Response音讯没有收到，网络会重发Paging音讯，并重新开场T3113计时。重试的次数在交换机中定义。Paging失败MSBTSBSCMSCClear CMDESTIN

37、(Loc Up Req)RR Connection EstablishmentRR Connection EstablishmentRR Connection EstablishmentAuthentication ProcedureAuthentication ProcedureAuthentication ProcedureCiphering ProcedureCiphering ProcedureCiphering ProcedureTMSI Realloc ProcedureTMSI Realloc ProcedureTMSI Realloc ProcedureLoc Up Accep

38、tChannel ReleaseDeactivate SACCHDISCRelease IndicationUARF Ch ReleaseLoc Up ReqLoc Up AcceptLoc Up AcceptChannel ReleaseRF Ch Release AckClear CMPST3210ET3210LU Type，MS ID，LAI，Classmark1，位置更新过程Location Update Request位置更新过程 A口位置更新后没有后续的Follow-on呼叫过程手机原来的LAC手机的TMSILocation Update Accept位置更新过程 A口新的LAC重

39、新分配的TMSI切换分为小区内切换IntraCell Internal Handover : 切换缘由 (按优先级排序)Cause 15 & 16 干扰切换(High level interference on UL or DL).Cause 10 & 11 : 同心圆内圆电平过低而向外园切换Too low level, inner zone (inner to outer zone HO, concentric cell) (UL & DL)Cause 13 : 同心圆外圆电平较高时向内圆切换Too high level on the UL and DL, outer zone (outer

40、 to inner zone HO, concentric cell)BSC内部小区间切换Intercell Internal Handover切换缘由 (按优先级排序)Cause 7 : 微小区BadSACCH切换Several consecutive Bad SACCH frames received (rescue microcell HO)Cause 17 & 18 : 微小区高门限切换Too low level in a microcell compared to a high threshold (UL & DL)Cause 2 & 4 : 质量切换Too Low Quality

41、(UL & DL)Cause 3 & 5 : 电平切换Too Low Level (UL & DL)Cause 6 : 太长间隔且换Too long MS-BS distanceCause 22: 扩站小区外小区太短间隔切换Too short MS-BS distanceCause20: 强迫直接重试Forced Direct RetryCause25: GPRS重定向GPRS Redirection 切换过程Cause 21: Preferred Band切换High level in neighbor cell in the preferred bandCause 14: 宏小区到微小区切

42、换High level in a neighbor microcell for macrocell to microcell HO.Cause 12: PBGT切换Power Budget (Better Cell HO)Cause 23: 话务切换Traffic HOCause 24: 综合捕捉切换General Capture HO同步切换Intra Cell切换部分Internal Inter Cell切换异步切换切换过程MSBTSBSCMSCMeasurement RepMeasurement ResIntra cell切换Phys Context ReqOCOCPhys Contex

43、t ConfOC : Old ChannelNC : New ChannelNCNCChannel Activation AckChannel Activation Assignment CommandAssignment CommandOCSABMEstablish IndicationUAOCNCNCNCAssignment CompleteNCAssignment CompleteHandover PerformedRF Channel RelOCRF Channel Rel Ack.OCST9108ET9108ST9103ET9103ST3107ET3107ST_RCR_ACKET_R

44、CR_ACK原信道上的TA、MS/BS_TxPwr被沿用到了新的信道上IntraCell HO总是用Assignment的过程来完成HO Cause，Cell ID，Chn TypeIntra Cell切换过程Assignment CommandIntra Cell切换过程 Abis原来的TCH信道新分配的TCH信道频点84TCH拥塞Intra Cell切换将不会发生T9108超时 : BTS对physical context request没有呼应之后的Channel Activation音讯中将不带TA和手机及BTS的发射功率信息T9103超时 : Channel Activation没有

45、回应Intra Cell切换过程将终止A接口上不会有任何音讯传送BSC向BTS发RF Channel Release音讯，释放新信道BSC收到Channel Activation Negative Acknowledge音讯Intra Cell切换过程将终止Channel Activation Negative Acknowledge有以下几种缘由 :Channel Already Activated (CAA): BSC向手机和BTS发信道释放音讯Radio Resource Not Available (RRNA) - Protocol error (PE) : BSC内部释放Reques

46、ted transcoding rate not supported (RTRNS) : BSC内部释放Encryption algorithm not implemented (EANI) : BSC内部释放O&M Intervention (OI) : BSC内部释放A接口上不会有任何音讯传送Intra Cell切换过程异常情况在原来的信道上如SDCCH信道收到Assignment Failure音讯 Intra Cell切换过程将终止A接口上不会有任何音讯传送BSC向BTS发RF Channel Release音讯，释放新信道Assignment Command的内容有误，手机发Assi

47、gnment Failure音讯到BSCIntra Cell切换过程将终止A接口上不会有任何音讯传送BSC向BTS发RF Channel Release音讯，释放新信道T3107超时BSC在A接口发Clear Request “Radio Interface Message FailureBSC向BTS发RF Channel Release音讯，释放新老信道构成切换掉话其它异常中断音讯Error ReportConnection Failure IndicationRelease IndicationError IndicationIntra Cell切换过程异常情况MSBTSservingB

48、SCMSCBTStargetMeas ReportMeas ResultHO Alarm & Candidate CellPhys Context ReqPhys Context ConfChannel ActivationChannel Act Ack.HO CommandHO CommandHO AccessHO DetectionSABMEstablish IndUAHandover CompleteHandover CompleteHandover PerformedRF Channel ReleaseRF Channel Rel. Ack.ST9108ET9108ST9103ET91

49、03ST3103ST3103ST3106ET3106ST_RCR_ACKET_RCR_ACKST200ET200原信道上的TA、被沿用到了新的信道上，而MS/BS_TxPwr将用最大功率在新的信道上发射AB，DCHCell，MA，MAIO，HSN，TS，TATA被采用Internal Inter Cell切换过程同步切换MSBTSservingBSCMSCBTStargetHO Alarm & Candidate CellChannel ActivationChannel Act Ack.HO CommandHO CommandHO AccessHO DetectionSABMEstablis

50、h IndUAHandover CompleteHandover CompleteHandover PerformedRF Channel ReleaseRF Channel Rel. Ack.ST9103ET9103ST3103ST3103ST3105ET3105Physical InfoST3124ET3124ST200ET200ST_RCR_ACKET_RCR_ACKPhys Context ReqPhys Context ConfST9108ET9108Meas ReportMeas Result没有Physical Cont Req过程，原信道上的TA不能被沿用到新的信道上丈量TAT

51、ATA被采用在RF信道释放前，有Physical Context Req过程Internal Inter Cell切换过程异步切换Internal Inter Cell切换过程A口HO Performed切换缘由目的小区TCH拥塞Internal Inter Cell切换将不会发生T9108超时同步切换同Intra Cell情况T9103超时同Intra Cell情况BSC收到Channel Activation Negative Acknowledge音讯同Intra Cell情况Internal Inter Cell切换过程异常情况在原来的信道上如SDCCH信道收到HO Failure音讯

52、 Internal Inter Cell切换过程将终止A接口上不会有任何音讯传送BSC向BTS发RF Channel Release音讯，释放新信道HO Command的内容有误，手机发HO Failure音讯到BSCInternal Inter Cell切换过程将终止A接口上不会有任何音讯传送BSC向BTS发RF Channel Release音讯，释放新信道T3103超时BSC在A接口发Clear Request “Radio Interface Message FailureBSC向BTS发RF Channel Release音讯，释放新老信道构成切换掉话其它异常中断音讯Error Re

53、portConnection Failure IndicationRelease IndicationError IndicationInternal Inter Cell切换过程异常情况MSBTSservingBSCservingMSCBTStargetMeas ReportMeas ResultHO Alarm & Candidate CellChannel ActivationChannel Act Ack.HO CommandHO CommandHO AccessHO DetectionSABMEstablish IndUAHandover CompleteHandover Compl

54、eteHO CompleteRF Channel ReleaseRF Ch. Rel. Ack.BSCtargetHO RequiredHO RequestHO Request Ack.HO CommandPhys InformationSCCP Con RequiredSCCP Con Conf.Clear CommandClear CompleteSCCP ReleasedSCCP Rel. Cmp.STrr2ET3124ETrr2ST_HO_REQ_LostST9103ST9103ST9113ST3103ET3103ST3124ST200ET200ST3106ET3106ST8ET8Ex

55、ternal Inter Cell切换过程异步切换ET9113ET_HO_REQ_LostExternal Inter Cell切换过程A口HO Required切换缘由目的小区External Inter Cell切换过程A口HO Command目的小区信息：BCCH/BSIC目的小区信道信息用于手机发HO Access手机切换后的初始发射功率External Inter Cell切换过程A口Clear CommandExternal Inter Cell切换过程A口HO Request 1 of 2信道描画支持的加密算法Classmark2External Inter Cell切换过程A口

56、HO Request 2 of 2原来的小区Priority和QueuingA中继的CIC目的的小区Classmark3External Inter Cell切换过程A口HO Request AckHO CommandExternal Inter Cell切换过程A口HO CompleteT8 超时效力BSC在A接口发Clear Request “Radio Interface Message Failure效力BSC向BTS发RF Channel Release音讯，释放老信道构成切换掉话T9113 Expiry目的BSC在A接口发HO Failure “Radio Interface Fa

57、ilure目的BSC向BTS发RF Channel Release音讯，释放新信道External Inter Cell切换过程异常情况MSBTSBSCMSCDisconnectDisconnectDisconnectReleaseReleaseReleaseRelease CompleteRelease CompleteRelease Complete手机触发的呼叫释放DisconnectDisconnectDisconnectReleaseReleaseReleaseRelease CompleteRelease CompleteRelease Complete网络触发的呼叫释放呼叫释放过程呼叫释放过程A口A口信令手机发起的呼叫释放过程呼叫释放DTAP层释放BSSM层释放SCCP层释放DisconnectMS触发的呼叫释放正常挂机呼叫释放过程A口A口信令网络发起的呼叫释放过程Disconnect网络触发的呼叫释放对方正常挂机DisconnectCause0001000Operator determined barring主叫过程中，主叫欠费停机0010000Normal