MSBTSBSCMSCChannel Request (RACH)Channel RequiredBSC 随 机 接 入 - 立 即 指配: 000008 、 000012小区 SDCCH- 立即指配请求 008000 、 008137Channel Activation (SDCCH)Channel Activation AcknowledgeImmediate Assignment CommandImmediate Assignment (AGCH)Establish Indication (CM-Service Request)BSC 整 体 立 即 指 配 成功: 000013小区 SDCCH- 立即指配成功008001 、 008003 、 008005 、008138、008141、(008142) Complete L3 Infomation (SCCP CR)CM Service RequestComplete L3 Infomation (SCCP CC)CM Service AcceptCM-Service Accept (DTAP)Assignment Procedure Signalling Connection Acknowledge BSC 整体成功的连接次数 000014Setup (SDCCH)SetupCall ProceedingCall ProceedingFigure
1 呼叫(主叫)SDCCH 基本信令流程图 MSBTSBSCMSCAssignment CompleteBSC 整体指配请求次数 000089小区 TCH 占用请求次数 008041 、 008042 、 008045Channel Activation (TCH)Channel Activation AcknowledgeRF Channel Release (Old