【正文】 。 通話接續(xù)時長分析，通過對信令流程進(jìn)行分段統(tǒng)計分析找出時長偏長原因。可通過對特定號碼或呼叫失敗信令進(jìn)行完整的信令流程跟蹤，對失敗信令消息的具體內(nèi)容進(jìn)行分析后得到確認(rèn)。 ?切換分析 通過 A口信令分析可定位由于交換數(shù)據(jù)問題導(dǎo)致的切換問題； 通過 ABIS口信令分析（分別收集源小區(qū)和目標(biāo)小區(qū) ABIS口信令）可發(fā)現(xiàn)無線參數(shù)設(shè)置和無線質(zhì)量問題（包括電平問題、質(zhì)量問題、載頻故障、鏈路不平衡、上行干擾等） ?其他問題分析 單通、竄話、回聲、斷噪等話音質(zhì)量問題。一方面可以對壞小區(qū)進(jìn)行定位，另外通過對大量問題事件的分析對參數(shù)設(shè)置策略可作出指導(dǎo)作用； 2）對各載頻各信道的測量報告進(jìn)行分析； 例 掉話分析 ?ABIS口分析 例 切換分析 ?ABIS口分析 ?A口分析 主要分析思路： 通過對特定呼叫（如特定號碼、特定小區(qū)）或?qū)ｉT進(jìn)行的撥打測試進(jìn)行信令跟蹤找出問題發(fā)生的環(huán)節(jié)，判斷可能原因后做進(jìn)一步分析；（例如單通、串話等問題） 對異常信令進(jìn)行篩選歸納，找出問題的共性并作進(jìn)一步的分析；（例如接續(xù)困難，異常拆鏈） 信令流程的統(tǒng)計分析，主要通過對信令流程中各環(huán)節(jié)的次數(shù)、時間間隔等進(jìn)行分析發(fā)現(xiàn)問題所在。 通過對測試手機的一些強制性命令，觀察此時的信令流程來分析切換困難、單通、回聲等系統(tǒng)問題。 TUP協(xié)議介紹 ISUP協(xié)議介紹 GSM 信令流程 呼叫接續(xù)流程； 位置更新流程； 切換流程 MSC MS BSC Channel activation ack Channel activation Encryption mand Channel required Complete Layer 3 Info. Authentication request Call proceeding Cipher Mode Complete SABM(cm_serv_req) Immediate assign mand establish indication BTS Channel request UA(cm_serv_req) Cipher Mode Command Immediate assignment Authentication response Setup Cipher Mode Command Cipher Mode Complete 主叫流程之一 呼叫接續(xù)流程 主叫流程之二 MS BSC BTS MSC Assignment Request Channel activation ack Assignment mand establish indication Assignment Complete Assignment Complete Deactivate SACCH Release request Release confirm RF Channle release RF Channel release ack Alerting Connect Connect acknowledge SABM UA Channel activation MS BSC BTS MSC 主叫流程之三 Channel Release Release Complete Release Clear Command RF Channle release DISC Deactivate SACCH RF Channel release ack Release Indication UA Disconnect Clear Complete 被叫流程之一 MS BSC BTS MSC Channel activation ack Channel activation Encryption mand Channel required Complete Layer 3 Info. Authentication request Call confirm Cipher Mode Complete SABM(pag_resp) Immediate assign mand establish indication Channel request UA(pag_resp) Cipher Mode Command Immediate assignment Authentication response Setup Cipher Mode Command Cipher Mode Complete Paging Command Paging Request Paging 被叫流程之二 MS BSC BTS MSC Assignment Request Channel activation ack Assignment mand establish indication Assignment Complete Assignment Complete Deactivate SACCH Release request Release confirm RF Channle release RF Channel release ack Alerting Connect Connect acknowledge SABM UA Channel activation 被叫不在服務(wù)區(qū) MS BSC BTS MSC Channel activation ack Channel activation Channel required Immediate assign mand Channel request Immediate assignment Paging Command Paging Request Paging Deactivate SACCH Release request Release confirm RF Channle release RF Channel release ack MS BSC Channel activation ack Channel activation Encryption mand Channel required Complete Layer 3 Info. Authentication request TMSI reallocation plete Cipher Mode Complete SABM(loc_upd_req) Immediate assign mand establish indication BTS Channel request UA(loc_upd_req) Cipher Mode Command Immediate assignment MSC Authentication response Location updating accept Cipher Mode Command Cipher Mode Complete 位置更新流程之一 位置更新流程 MS BSC BTS MSC 位置更新流程之二 Channel Release Clear Command RF Channle release DISC Deactivate SACCH RF Channel release ack Release Indication UA Clear Complete MS Measurement report Measurement result Channel Active Channel Active Ack Channel Active Nack ASSIGN COMMAND SABM UA EST IND RF Channel REL RF Channel REL Ack HANDOVER PERFORMED BTSA BSC MSC ASSIGN FAILURE ASSIGN COMPLETE 小區(qū)內(nèi)切換 切換流程 HO PERFORMED Measurement report Measurement result MS Channel Active Channel Active Ack Channel Active Nack HOCOMMAND HOACCESS PHYS INFO HODETECTION SABM UA EST IND HO FALURE HOCOMPLETE RF Channel REL RF Channel REL Ack BTSA BSC MSC BTSB MS BSC 內(nèi)部切換 BSC間切換 信令流程中重要定時器介紹 重要信令消息內(nèi)容詳解 UM口重要信令消息； ABIS口重要信令消息； A口重要信令消息； System information type 2 空閑模式下與服務(wù)小區(qū)同頻段的鄰小區(qū)頻點集； System information type 2ter 空閑模式下與服務(wù)小區(qū)不同頻段的鄰小區(qū)頻點集 System information type 5 專用模式下與服務(wù)小區(qū)同頻段的鄰小區(qū)頻點集； System information type 5ter 專用模式下與服務(wù)小區(qū)不同頻段的鄰小區(qū)頻點集 UM口 UM口 CMREQ或 PAGRES UM口 SETUP UM口 Assighment