倘若抓取到的QXDM日志报Implicitly detached错误，这是由NW决定的，UE是被动的。

//snip some OTA log

Detailed Analysis:
//cell infor
18:18:48.277094 LTE RRC Serving Cell Info Log PktLength: 45
Physical cell ID = 283
DL FREQ = 66786
UL FREQ = 132322
DL Bandwidth = 20 MHz
UL Bandwidth = 20 MHz
Cell Identity = 15869442
Tracking area code = 30599
Freq Band Indicator = 66
MCC = 310
Number of MNC digits = 3
MNC = 260

//periodic TAU ok
18:23:05.970056 LTE NAS EMM Plain OTA Outgoing MessageTracking area update request Msg
eps_update_type = 3 (0x3) (periodic updating)
18:23:06.097020 LTE NAS EMM Plain OTA Incoming MessageTracking area update accept Msg

//the same cell
18:59:41.961090 LTE RRC Serving Cell Info Log PktLength: 45
Physical cell ID = 283
DL FREQ = 66786
UL FREQ = 132322
DL Bandwidth = 20 MHz
UL Bandwidth = 20 MHz
Cell Identity = 15869442
Tracking area code = 30599
Freq Band Indicator = 66
MCC = 310
Number of MNC digits = 3
MNC = 260

//NW rej periodic TAU with cause_value = 10 (0xa) (Implicitly detached)
19:17:06.136007 LTE NAS EMM Plain OTA Outgoing MessageTracking area update request Msg
eps_update_type = 3 (0x3) (periodic updating)
19:17:06.253119 LTE NAS EMM Plain OTA Incoming MessageTracking area update reject Msg
cause_value = 10 (0xa) (Implicitly detached)

Refer to 3GPP 24.301,
Cause #10 – Implicitly detached
This EMM cause is sent to the UE either if the network has implicitly detached the UE, e.g. after the implicit detach timer has expired, or if the EMM context data related to the subscription does not exist in the MME e.g. because of a MME restart, or because of a periodic tracking area update request routed to a new MME.