割接后系统性能监控

割接后系统性能监控本文分析系统性能是中国移动公司的指标计算公式为主线,从呼叫流程开始针对相关的统计项作重点分析说明,从而找到解决问题的各种方法.一.无线接通率:无线接通率＝（1－SDCCH_BLK_RATE）×（1－TCH_BLK_RATE）×100％SDCCH_BLK_RATE=ALLOC_SDCCH_FAIL/ALLOC_SDCCH(+ALLOC_SDCCH_FAIL)TCH_BLK_RATE=MA_CMD_TO_MS_BLK/MA_REQ_FROM_MSC.提高无线接通率的办法是降低SDCCH_BLK_RATE与TCH_BLK_RATE.1.SDCCH_BLK_RATE与TCH_BLK_RATE手机通过RACH向基站发起服务请求，基站从AGCH上给手机指定SDCCH，手机占上SDCCH，向网络发出服务连接请求。这就是SDCCH的占用过程.EstabishindicateUAL3initmsgMSRSSCRMRRSMSSMMSCOK_ACC_PROC_SUC_RACHACCESS_PER_RACHINV_EST_CAUSE_ON_RACHCHAN_REQ_CAUSE_ATMPTChannelRequiredChannelRequiredChannelRequiredReceivedChannelassignmentAlloc_sdcchALLOC_SDCCH_FAILCHAN_REQ_MS_BLKDChannelactivationImmediateChannelrejectChannelactivationacknowledgeImmediateassignmentChannelImmediateassignmentChannelRr_t3101SABM(L3initMSG)StopRr_t3101Ok_acc_procChan_req_ms_fallInitialL3info.CRMS传送一个信道请求消息(智能信息,建立原因值,随机参考),打包在接入突发序列中,信道编码器对其解码.正确解码后被送到RSS-L1OK_ACC_PROC_SUC_RACH;ACCESS_PER_RACH增值.收到信道请求消息,RSSABIS验证信道建立原因值有效性,无效加1,有效就格式化消息送到RRSM.一旦RRSM接收到信道需求的消息,将试图把MS建立在一个专用信道上,CHAN_REQ_CAUSE_ATMPT作出标记.成功分配SDCCH后,CRM中的ALLOC_SDCCH增值.每当CRM试图分配一个空闲的SDCCH,却由于SDCCH忙而禁止时,ALLOC_SDCCH_FAIL值增加,当由于资源短缺而拒绝SDCCH的切换时,在目标小区中,也会增加.（在没有SDCCH切换时，alloc_sdcch_fail=chan_req_ms_blk）当收到来自CRM的立即分配拒绝消息时,CHAN_REQ_MS_BLKD递增.RR_T3101定时期满没有收到建立指示,CHAN_REQ_MS_FALL做标记.若存在较大的alloc_sdcch_fail，说明SDCCH拥塞严重，常用的解决方法是：增加SDCCH数目,特别是铁路高速公路旁边的基站.较大干扰会造成SDCCH,TCH拥塞,故一定要排除干扰.减小该cell的C1（增大rxlev_access_min）.采用动态分配SDCCH的算法.2TCH拥塞:CCCREFCR:conn_req_to_mscConn_refusedMSCSSMRRSMCRMRSSAssignmentrequstInitiateAssignmentAssignmentresourcerequstALLOC_TCH_FAIL/无资源ResourcenotavailableUnsuccessfulassignmentMA_CMD_TO_MS_BLKAssignmentfailureMA_REQ_FROM_MSCALLOC_TCHAssignmentchannelassignedPhysicalContextRequestPhysicalContextConfirmChannelActivationChannelActivationAcknowledgeDataRequest(AssignmentCommand)AssignmentCompleteAssignmentSuccessfulDataIndication(AssignmentFailure)MA_FAIL_FROM_MSConnectionRequestTOTAL_CALLSMA_COMPLETE_TO_MSCAssignmentCommandStartT10MA_CMD_TO_MSDataIndication(AssignmentComplete)StopT10AssignmentFailureSwitchResponseSuccessAssignmentCompleteUnsuccessfulAssignmentStoptimerassign_successfulIfT10expires,whichmeanstheMScan’ttunetotheTCHanditalsofailstoretunbacktotheSDCCH.MSRSSCRMRRSMSSMMSCSM当SDCCH上的鉴权,加密和呼叫建立完成之后,MSC将开始分配进程为手机分配TCH。交换机发分配需求消息给SSM，消息中带有交换机指定的CIC。BSC的SSM收到分配需求后记为ma_req_from_msc.BSC的CRM随即分配TCH，如果此时无可用TCH，则记ma_cmd_to_ms_blk，同时记alloc_tch_fail。注意：alloc_tch_fail还会在切换时记数。正常情况下，TCH的拥塞应该为0，如果出现拥塞，则主要的解决方法有：打开该小区往其它小区的拥塞切换。增大天线俯仰角,降低功率,减小话务量的吸收(尽量不采用).打开该小区的动态配置功能。使该小区往相邻小区的切换更容易。增加TCH.是否有断站.检查是否是外部干扰引起的.提高无线接通率的办法是降低SDCCH_BLK_RATE与TCH_BLK_RATE.只要把握尽量减小SDCCH,TCH的拥塞,无线接通率很容易达到99.7%(满分).二.切换成功率:(out_intra_bss_ho_suc+out_inter_bss_ho_suc+in_intra_bss_ho_suc+in_inter_bss_ho_suc)/out_intra_bss_ho_atmpt+out_inter_bss_ho_atmpt+in_intra_bss_ho_suc+in_intra_bss_ho_lostms+in_intra_bss_ho_return+in_intra_bss_ho_cleared+ho_req_msc_okINTRA_BSS_HO_SUC+INTER_BSS_HO_SUC/BSS_HO_ATMP+由于INTRA_CELL_HO不在考核范围内,故对其不作分析.当HDPC(INRSS)向RRSM发送切换认可消息(含原因&合格的相邻小区)后,RSS将启动切换程序.RRSM把消息作为切换认可受到消息送给SSM.,BSC决定何种切换1.BSS内切换:MSRSS(S)CRM(S)RRSM(S)SSMMSCHo_recognised切换认可Ho_rec_receivedRRSM(TCRM(TRSS(TInterhorequstHo_channelassignedChannelactiveChannelactiveackMSpowercontrolHoallocationIN_INTRA_BSS_NC_ATMPTOUT_INTRA_BSS_HO_REQInitiateHOOUT_INTRA_BSS_HO_ATMPTOUT_HO_CAUSE_ATMPTPTINTERBAND_ACTIVITYHO_CMDHO_CMDFACCHHoaccessFACCHHoaccessHoaccessHoaccessPhysinfoSABMUAHo_cmpltHo_detectionEstabishindicationHo_cmpltHo_detectionreceivedHo_succSMTransrequstSwitchrespondOUT_HO_NCSUCOUT_INTRA_BSS_HO_SUCIN_INTRA_BSS_HO_SUCINTRA_BSS_HO_CAUSE_SUCHo_performedOUT_HO_NC_CAUSE_ATMPTOUT_HO_CAUSE_ATMPTINTERBAND_ACTIVITYInterhoRequestStateT3103StopT3103HoresourcenotavalibleHO_FAI_NO_RESOURCEOUT_INTRA_BSS_HO_PRI_BLKInitiateHOHOcommandUnsuchoOUT_INTRA_BSS_HO_RETURNOUT_INTRA_BSS_EQUIP_FAILIN_INTRA_BSS_HO_RETURNIN_INTRA_BSS_EQUIP_FAILHOfailureIftimerexpireChannelreleasedIftimerexpireChannelreleasedIN_INTRA_BSS_HO_LOSTMST3103exoire,clearrequstOUT_INTRA_BSS_HO_LOSTMSCLR_REQ_TO_MSC成功切换:每次SSM决定进行BSS内切换,OUT_INTRA_BSS_HO_REQ就进行标记.SSM一旦收到由目标RRSM送来的切换分配消息中规定的目标资源后,通过发送开始切换消息来启动MS从源小区向目标小区的切换.发送该消息后,OUT_INTRA_BSS_HO_ATMPT对于源小区递增.源RRSM收到开始切换消息就要格式化通过发往MS的空间接口切换命令(在FACCH上发送,并向MS提供目标TCH的详细情况).MS将改变其空间接口特性,试图在L1与目标RSS连接起来,然后L2与目标RSS连接.若不同步,会在试图建立L2之前发送4个连续的L1接入突发序列.MS在与RSS连接后,会发送一个L3切换完成消息,此消息作为切换成功消息传至SSM,SSM收到此消息后,格式化并向MSC发送切换完成的消息.IN_INTRA_BSS_HO_SUC&OUT_INTRA_BSS_HOSUC递增.切换失败:当SSM把开始切换消息发给源RRSM时,T3103开始运转,在成功的情况下SSM会在期满前收到从目标RRSM切换成功的消息.MS一收到开始切换命令就改变其本身特性,试图与目标RSS建立L1链路在异步的情况下,MS开启T3124,期满未收到物理消息或在切换完成消息发送前有底层故障,那么MS终止使用新的TCH,返回旧的TCH,MS发出切换失败消息,源RRSM告知SSMT,3103停,源小区OUT_INTRA_BSS_HO_RETURN与目标小区IN_INTRA_BSS_HO_RETURN递增.OUT_INTRA_BSS_HO_LOSTMS为在一个切换尝试过程中不能捕获新的源小区的信道而导致MS不能返回原始信道的次数,即为掉话.IN_INTRA_BSS_HO_CLR为BSS内部切换过程中呼叫被清除的次数.BBS间切换:HandoverRequiredCR(HandoverRequest)HandoverRequestHandoverChannelAssignedChannelActivationChannelActivationAckHandoverAllocationConnectionRequestSwitchResponseOUT_INTER_BSS_REQ_TO_MSCStartT7HO_REQ_MSC_OKHandoverRequestAckHandoverCommandStopT7OUT_INTER_BSS_HO_ATMPTOUT_HO_NC_CAUSE_