Current Channel Number: 62 Current Time Slot: 1
Attempted Cellular System: GSM 900 目标小区情况描述 Attempted Channel Number: 92 Attempted Time Slot: 2
3 Layer 3 Downlink 18:53:13.451 FACCH PHYSICAL INFORMATION
由于是非同步切换，里边包含计算的TA值，用于同步。在发送物理消息时，系统同时启动T3105定时器，在收到移动台正确的SABM帧应答前，在T3105超时后，重启并重新发送物理消息。 Timing Advance (hex data: 03)
Timing advance value: 3 (= 11 microseconds) 4 Layer 2 Uplink 18:53:13.453 FACCH SABM-CMD 如上所述，SABM为确认帧
5 Layer 3 Uplink 18:53:13.572 FACCH HANDOVER COMPLETE
移动台发送切换完成的消息给BSC，此后他会将目标小区发送一条切换完成信息，此信息部携带任何信息，发出后，手机才不会返回到原来的信道。如果移动台没有收到目标小区发送的物理消息，或UA响应帧，则会在原信道上发送一条切换失败的信息。 6 Handover Success18:53:13.572 From BTS: To BTS: BSIC: 37 12 Carrier: 62 92 Time Slot: 1 2 Timing Advance: 3 2
Local Area Code: 14101 14101 Cell ID: 41101 1633 RX Level Full: -81 -74 RX Level Sub: -80 -74 RX Quality Full: 3 0 RX Quality Sub: 0 0 MS Power: 5 6
上述38-43为一非同步切换过程
§3异常信令流程
§3.1由设备原因引起呼叫建立失败信令流程
（集团公司测试规范中，试呼次数：以channel request和CM service request同时出现来确定试呼开始。） 1 Call Attempt 19:31:09.577
2 Layer 3 Uplink 19:31:10.126 RACH CHANNEL REQUEST 3 Layer 3 Downlink 19:31:10.330 CCCH IMMEDIATE ASSIGNMENT 4 Layer 3 Uplink 19:31:10.468 SDCCH CM SERVICE REQUEST
5 Layer 3 Downlink 19:31:10.902 SDCCH AUTHENTICATION REQUEST 6 Layer 3 Uplink 19:31:11.642 SDCCH AUTHENTICATION RESPONSE 7 Call Failed 19:31:11.642 State:Test system failure
8 Layer 3 Downlink 19:31:11.854 SDCCH CM SERVICE ACCEPT 9 Call Attempt 19:31:12.347
§3.2被叫做位置更新造成主叫呼叫建立失败信令流程 主叫 被叫
Call Attempt 11:13:43.737 呼叫尝试
Layer 2 Uplink 11:13:44.297 RACHRANDOM_ACCESS_BURST 信道请求 Layer 3 Uplink 11:13:44.297 RACH CHANNEL REQUEST
Layer 3 Downlink 11:13:44.473 CCCH IMMEDIATE ASSIGNMENT 立即指配 Layer 3 Uplink 11:13:44.714 SDCCH CM SERVICE REQUEST 服务类型请求 Layer 3 Downlink 11:13:45.151 SDCCH AUTHENTICATION REQUEST 鉴权请求 Layer 3 Uplink 11:13:45.890 SDCCH AUTHENTICATION RESPONSE 鉴权响应 Layer 3 Downlink 11:13:46.093 SDCCH CM SERVICE ACCEPT 服务类型请求回应 Layer 3 Uplink 11:13:46.597 SDCCH SETUP 分配SD
Layer 3 Downlink 11:13:46.799 SDCCH CALL PROCEEDING 开始呼叫
Layer 3 Downlink 11:13:47.269 SDCCH ASSIGNMENT COMMAND 业务信道分配 Layer 3 Uplink 11:13:47.458 FACCH ASSIGNMENT COMPLETE 业务信道分配完成 Call Connect Success 11:13:47.458 呼叫成功,表示主叫接入网络 被叫做位置更新 Cell Reselection 11:13:50.490 Old Cellular System: GSM 900 Old LAC: 14081
Old Cell Identification: 41701
New Cellular System: GSM 900 New LAC: 14129
New Cell Identification: 1413
立即指配 Layer 3 Downlink 11:13:52.953 CCCH IMMEDIATE ASSIGNMENT Layer 2 Uplink 11:13:53.005 RACH RANDOM_ACCESS_BURST 信道请求
原因:用于位置更新 Layer 3 Uplink 11:13:53.005 RACH CHANNEL REQUEST M Establishment Cause (hex data: 07)
Meaning of establishment cause: Location updating and the network sets NECI bit to 1
立即指配 Layer 3 Downlink 11:13:53.092 CCCH IMMEDIATE ASSIGNMENT
位置更新请求 Layer 3 Uplink 11:13:53.211 SDCCH LOCATION UPDATING REQUEST TOM解释 Location Update Attempt 11:13:53.211
位置更新请求相应 Layer 3 Downlink 11:13:53.650 SDCCH LOCATION UPDATING ACCEPT 位置更新请求相应 Location Update Accepted 11:13:53.650 Old LAC: 14081 New LAC: 14129 Mobile Country Code: 460 Mobile Network Code: 0
TMSI重分配 Layer 3 Uplink 11:13:53.917 SDCCH TMSI REALLOCATION COMPLETE 信道释放 Layer 3 Downlink 11:13:54.119 SDCCH CHANNEL RELEASE 回到空闲模式 Layer 2 Uplink 11:13:54.389 SDCCH DISC-CMD Layer 3 Downlink 11:13:59.696 FACCH ALERTING 振铃
按正常的信令流程,此时系统应下发CONNECT,移动台应上发CONNECT ACKNOWLEDGE.按照集团公司城市DT测试规范,只有出现这两条信令中的任一条,才被计为一次通话.所以此处应该判定为呼叫建立失败. Call Connect Success 11:13:59.696 呼叫连接成功,TOM解释
此后一直到11:14:40,系统向主叫移动台播放语音提示\你所拨打的用户暂时无法接通\Layer 3 Downlink 11:14:40.671 FACCH DISCONNECT M Cause (hex data: 02e292)
Cause (18): No user responding 系统下发拆线信息 原因:
被叫无应答
Layer 3 Uplink 11:14:40.685 FACCH RELEASE 信令链路释放 Call Disconnect 11:14:40.685
Status:Dropped call (i.e., network release) Phone Number: 13673640441 Time From Attempt: 57 CC Cause: 18 含有拆线原因
Layer 3 Downlink 11:14:40.822 FACCH RELEASE COMPLETE 释放完成 Layer 3 Downlink 11:14:40.928 FACCH CHANNEL RELEASE 信道释放 Layer 2 Uplink 11:14:40.942 FACCH DISC-CMD 回到空闲模式
此次呼叫失败的原因是因为被叫做位置更新,手机位置更新后,拥有了新的TMSI.可是主叫仍然呼叫的是原来系统存储的TMSI,所以无法呼叫到用户. §3.3由于拥塞造成的呼叫建立失败信令流程 Call Failed 19:07:53.399 7 15 -1 State: TCH blocking Time From Attempt: 15 OS RAS Cause: n/a
在此条信令中,后边的参数7指示是由于拥塞造成的呼叫建立失败. §3.4由于被叫鉴权被拒绝造成主叫呼叫建立失败信令流程 主叫 被叫
Call Attempt 呼叫尝试
Layer 2 Uplink RACHRANDOM_ACCESS_BURST 信道请求 Layer 3 Uplink RACH CHANNEL REQUEST
Layer 3 Downlink CCCH IMMEDIATE ASSIGNMENT 立即指配 Layer 3 Uplink SDCCH CM SERVICE REQUEST 服务类型请求 Layer 3 Downlink SDCCH AUTHENTICATION REQUEST 鉴权请求 Layer 3 Uplink SDCCH AUTHENTICATION RESPONSE 鉴权响应 Layer 3 Downlink SDCCH CM SERVICE ACCEPT 服务类型请求回应 Layer 3 Uplink SDCCH SETUP 分配SD
Layer 3 Downlink SDCCH CALL PROCEEDING 开始呼叫
Layer 3 Downlink SDCCH ASSIGNMENT COMMAND 业务信道分配 Layer 3 Uplink FACCH ASSIGNMENT COMPLETE 业务信道分配完成
Call Connect Success 呼叫成功,表示主叫接入网络
立即指配 Layer 3 Downlink CCCH IMMEDIATE ASSIGNMENT Layer 2 Uplink RACH RANDOM_ACCESS_BURST 信道请求
原因:用于响应呼叫 Layer 3 Uplink RACH CHANNEL REQUEST 立即指配 Layer 3 Downlink CCCH IMMEDIATE ASSIGNMENT Layer 3 Downlink SDCCH AUTHENTICATION REQUEST Layer 3 Uplink SDCCH AUTHENTICATION RESPONSE Layer 3 Downlink SDCCH IDENTITY REQUEST Layer 3 Uplink SDCCH IDENTITY RESPONSE Layer 3 Downlink SDCCH AUTHENTICATION REJECT Layer 3 Downlink FACCH DISCONNECT Call Disconnect 含有拆线原因
Layer 3 Downlink SDCCH CHANNEL RELEASE
Layer 3 Downlink FACCH RELEASE COMPLETE 释放完成 Layer 3 Downlink FACCH CHANNEL RELEASE 信道释放 Layer 2 Uplink FACCH DISC-CMD 回到空闲模式 §3.5无线链路超时造成掉话信令流程 主叫 被叫
Call Attempt 17:59:12.061
Layer 2 Uplink 17:59:12.625 RACHRANDOM_ACCESS_BURST Layer 3 Uplink 17:59:12.625 RACH CHANNEL REQUEST Layer 3 Downlink 17:59:12.710 CCCHIMMEDIATE ASSIGNMENT Layer 3 Uplink 17:59:12.895 SDCCH CM SERVICE REQUEST Layer 3 Downlink 17:59:13.332 SDCCHAUTHENTICATION REQUEST Layer 3 Uplink 17:59:14.074 SDCCHAUTHENTICATION RESPONSE Layer 3 Downlink 17:52:14.275 SDCCH CM SERVICE ACCEPT Layer 3 Uplink 17:52:14.780 SDCCH SETUP
Layer 3 Downlink 17:52:14.981 SDCCH CALL PROCEEDING Layer 3 Downlink 17:52:15.450 SDCCHASSIGNMENT COMMAND