eDRX extends the paging cycle in the idle RRC state, trading response latency for lower average current on an otherwise idle cellular link.
eDRX is requested through AT+CEDRXS. The currently negotiated eDRX
parameters are read back with AT+CEDRXRDP.
Paging Time Window
The proprietary %PTWEDRXS AT command configures the Paging Time Window
(PTW) jointly with the requested eDRX parameters. PTW can be requested in the range 1.28 s
to 20.48 s, and determines how long the UE monitors for paging within each eDRX cycle.
Operator-specific minimums may also apply, such as a minimum of 5.12 seconds.
Relationship to PSM
eDRX and PSM are complementary and can be enabled simultaneously. The network and the application together decide the balance.