Airplane mode in LTE/UMTS/GSM ?

Question

1- Which messages gets exchanged between UE and network when enabling airplane mode in Idle/connected mode in LTE or UMTS?
2- Can we initiate Emergency call when in Airplane mode ?

Comments

Does the device knows what sim is in the device after enabling airplane mode?

Answer 1

Hi,

As per my understanding If you keep it in airplane mode then you cannot call even a emergency number. If you try in smartphone that will unlock airplane mode then it will try to call.

when you keep airplane mode UE will send detach request then it will move to detached state.

Comments

I just executed this case and observed below scenario;
1- UE in airplane mode
2-Signals get off
3-Initiated Emergency no
4-After a few sec,its camping on network and initiates emergency call.

Answer 2

If you are enabling Airplane Mode in UE:

1) If UE connected to Internet and IMS PDN: UE will send PDN Disconnect Request for IMS PDN and then sends the Detach Request.

2) If UE connected to only Internet PDN (Initial Attach): It Just sends Detach Request and response NW will send Detach Accept

If Airplane Mode is ON and Initiate a Emergency Call: UE will turn OFF the Airplane Mode and tries to attach on LTE first and then does the further signalling for emergency PDN