14.4.2 HS-DSCH DRX operation with second DRX cycle in CELL_FACH

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

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

For the HS-DSCH DRX operation in CELL_FACH, the UTRAN indicates 1^st inactivity time, 2^nd inactivity time, 1^st DRX cycle length, 2^nd DRX cycle length; 1^st RX burst length and 2^nd RX burst length in case of 2-level DRX. For the HS-DSCH DRX operation in CELL_FACH, the UTRAN indicates 2^nd inactivity time, 2^nd DRX cycle length and 2^nd RX burst length in case of 1-level DRX. 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.

Figure 14.4.2-0a: HS-DSCH DRX in CELL_FACH with 2-level DRX

Figure 14.4.2-0b: HS-DSCH DRX in CELL_FACH with 1-level DRX

The HS-DSCH DRX operation in CELL_FACH state is initialized when the 1^st or 2^nd inactivity timer expires. The 1^st 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 1^st inactivity time configured. Once the 1^st inactivity timer has expired, the UE may choose not to receive HS-DSCH for a given time within the period of the configured 1^st DRX cycle length. The UE shall receive HS-DSCH for the 1^st RX burst length of the 1^st DRX cycle length configured. In case of 2-level DRX the 2^nd inactivity timer is triggered, when the 1^st inactivity timer expires. Once the 2^nd inactivity timer has expired, the UE may choose not to receive HS-DSCH for a given time within the period of the configured 2^nd DRX second cycle length. The UE shall receive HS-DSCH for the 2^nd RX burst length of the 2^nd DRX cycle length configured.

This operation is illustrated in Figure 14.4.2-1.

The UE shall interrupt DRX operation in CELL_FACH state and continuously receive HS-DSCH, if data transmission activity is initiated. The UE shall also interrupt DRX operation in CELL_FACH state upon reception of an HS-SCCH order for NodeB triggered HS-DPCCH transmission during either of the 1^st or 2^nd Rx burst lengths.

Figure 14.4.2-1: Discontinuous HS-DSCH reception with second DRX cycle in CELL_FACH state with 2-level DRX

Figure 14.4.2-2: Discontinuous HS-DSCH reception with second DRX cycle in CELL_FACH state with 1-level DRX