Discontinuous Reception (DRX) reduces receiver activity in the RRC the IDLE state. Connected DRX applies the same principle during an active RRC connection and is managed transparently by the modem.
IDLE DRX
In the RRC IDLE state, the modem wakes periodically at the shorter of the USIM-configured or the network-configured DRX cycle to monitor the paging channel. IDLE DRX parameters are set by the network, and no host AT command changes them. Using eDRX extends the paging cycle beyond the short DRX cycles.
Connected DRX
Connected DRX is negotiated between the device and the network per the active RRC configuration and is handled by the modem. The modem firmware controls how System ON IDLE is used between the connected-DRX on-duration windows.
The host influences this decision through %MODULECFG="pmuInCdrx":
- 0 — do not enter deep sleep during connected DRX
- 1 — allow deep sleep during connected DRX (default)