14.4.1 HS-DSCH DRX operation in CELL_FACH state

25.3083GPPHigh Speed Downlink Packet Access (HSDPA)Overall descriptionRelease 17Stage 2TS

For the HS-DSCH DRX operation in CELL_FACH, the UTRAN indicates an inactivity time, a DRX cycle length and a RX burst length. This information is stored by the UE for use when in CELL_FACH state. The HS-DSCH DRX operation in CELL_FACH state is only possible when the UE has a dedicated H-RNTI configured.

The HS-DSCH DRX operation in CELL_FACH state is initialized when the inactivity timer expires. The inactivity timer is triggered whenever no data transmission activities are ongoing. At this point, the UE is shall continuously receive HS-DSCH for the length of the inactivity time configured. Once the inactivity timer has expired, the UE may choose not to receive HS-DSCH for a given time within the period of the configured DRX Cycle. The UE shall receive HS-DSCH for the RX burst length of the DRX Cycle configured. This operation is illustrated in Figure 14.4.1-1.

The UE shall interrupt DRX operation in CELL_FACH state and continuously receive HS-DSCH, if data transmission activity is initiated.

Figure 14.4.1-1: Discontinuous HS-DSCH reception in CELL_FACH state