Discontinuous Reception (DRX)

UEs in idle mode may use Discontinuous Reception (DRX) in order to reduce power consumption.

Using DRX, the UE only listens to the PICH at certain predefined times i.e. at its Paging Occasions.

Each PICH frame consists of a number of Paging
Indicators (PIs).

Every time the UE listens to the PICH, it gets information about if it should wake up (PI=1) and also read the SCCPCH carrying paging information or continue to sleep (PI=0).