5.13 Control channel discontinuous reception procedures

25.2243GPPPhysical layer procedures (TDD)TS

If the higher layers set CONTROL_CHANNEL_DRX_STATUS to TRUE (as described in [15]) and Enabling_Delay is configured to be finite value, after Enabling_Delay radio frames have passed, UE_ DRX_Enabled is TRUE. Or if the higher layers set CONTROL_CHANNEL_DRX_STATUS to TRUE and Enabling_Delay is configured to be infinity, after the UE has received DRX activation order via HS-SCCH order, UE_DRX_Enabled is TRUE. Otherwise UE_ DRX_Enabled is FALSE.

Whether discontinuous downlink HS-SCCH reception operation or discontinuous downlink E-AGCH reception operation is applied is determined by the setting of HS_SCCH_DRX_Active and E_AGCH_DRX_Active as follows:

HS_SCCH_DRX_Active shall be set to TRUE while UE_ DRX_Enabled is TRUE and discontinuous downlink HS-SCCH reception is activated. Otherwise, HS-SCCH _DRX_Active shall be set to FALSE.

Discontinuous downlink HS-SCCH reception shall be activated at the time when UE_ DRX_Enabled is set to TRUE, and may be further deactivated or activated by layer 1 HS-SCCH orders (see section 5.13.2).

E_AGCH_DRX_Active shall be set to TRUE while UE_DRX_Enabled is TRUE, E-AGCH DRX information is configured and discontinuous downlink E-AGCH reception is activated. Otherwise, E_AGCH_DRX_Active shall be set to FALSE.

Discontinuous downlink E-AGCH reception shall be activated at the time when UE_ DRX_Enabled is set to TRUE and E-AGCH DRX information is configured and may be further deactivated or activated by layer 1 HS-SCCH orders.

The higher layers define the discontinuous reception procedures using the following parameters (defined in [15]):

HS_SCCH_DRX Offset: HS-SCCH reception pattern offset in subframes.

E_AGCH_DRX Offset: E-AGCH reception pattern offset in subframes.

Enabling_Delay: ensures that the HS-SCCHs and E-AGCHs are received continuously for Enabling_Delay radio frames after CONTROL_CHANNEL_DRX_STATUS is set to TRUE.

HS_SCCH_DRX cycle: HS-SCCH reception pattern length in subframes.

E_AGCH_DRX cycle: E-AGCH reception pattern length in subframes.

Inactivity_Threshold_for_HS_SCCH_DRX_cycle: For single carrier HS-DSCH reception, when HS_SCCH _DRX_Active is TRUE, this timer shall be started or restarted in the same subframe as the HS-SICH corresponding to an HS-PDSCH reception.

For multi-carrier HS-DSCH reception, this timer should be maintained per UE. When HS_SCCH _DRX_Active is TRUE, this timer shall be started or restarted in the same subframe as the HS-SICH on any configured carrier corresponding to an HS-PDSCH reception.

E_AGCH_Inactivity_Monitor_Threshold: For single carrier E-DCH transmission, when E_AGCH_DRX_Active is TRUE, this timer shall be started or restarted in the same subframe as the E-HICH which contains the HARQ-ACK corresponding to the latest scheduling information indicating the TEBS equals zero. If the UE is transmitting SI only MAC-e PDU with TEBS equals zero and the UE is monitoring E-AGCHs only in the E-AGCH reception pattern, this timer shall not be started or restarted.

For multi-carrier E-DCH transmission, this timer should be maintained per UE. When E_AGCH_DRX_Active is TRUE, this timer shall be started or restarted in the same subframe as the E-HICH on any configured carrier which contains the HARQ-ACK corresponding to the latest scheduling information indicating the TEBS equals zero. If the UE is transmitting SI only MAC-i PDU with TEBS equals zero and the UE is monitoring E-AGCHs only in the E-AGCH reception pattern on all configured carriers, this timer shall not be started or restarted.

5.13.1 Discontinuous downlink reception

The HS-SCCH reception pattern is the same for all the configured carriers of the UE and is derived from a discontinuous reception subframe numbering as follows.

The HS-SCCH reception pattern is the set of subframes whose HS-SCCH discontinuous reception radio frame number CFN and subframe number subframe number verify:

((2*CFN – HS_SCCH_DRX Offset + subframe number) MOD HS_SCCH_DRX cycle) = 0

For the first subframe within each radio frame, the subframe number shall be set to 0. For the second subframe within each radio frame, the subframe number shall be set to 1.

When HS_SCCH_DRX_Active is FALSE, the UE shall monitor HS-SCCHs continuously according to rules defined in the subclause 5.9.3.

When HS_SCCH_DRX_Active is TRUE and the timer Inactivity Threshold for HS-SCCH DRX cycle is not configured by higher layers, the UE shall monitor the HS-SCCH subframes in the HS-SCCH reception pattern on all configured carriers.

When HS_SCCH_DRX_Active is TRUE and the timer Inactivity Threshold for HS-SCCH DRX cycle is configured by higher layers, the UE is required to monitor the HS-SCCHs in the UE’s HS-SCCH set on all configured carriers continuously when the timer is running. The UE shall only monitor the HS-SCCH subframes in the HS-SCCH reception pattern on all configured carriers when the timer is expired.

The E-AGCH reception pattern is the same for all the configured carriers of the UE and is the set of subframes whose E-AGCH discontinuous reception radio frame number CFN and subframe number verify:

((2*CFN – E_AGCH_DRX Offset + subframe number) MOD E_AGCH_DRX cycle) = 0

When E_AGCH_DRX_Active is FALSE and E-AGCH DRX information is configured, UE shall monitor E-AGCHs continuously.

When E_AGCH_DRX_Active is FALSE and the E-AGCH DRX information is not configured, UE shall monitor E-AGCHs according to rules defined in the subclause 5.11.3.

When E_AGCH_DRX_Active is TRUE and TEBS is larger than zero, the UE shall monitor the E-AGCHs on all configured carriers continuously.

When E_AGCH_DRX_Active is TRUE and TEBS is equal to zero, the UE is required to monitor the E-AGCHs in the UE’s E-AGCH set on all configured carriers continuously until the subframe when the timer E_AGCH_Inactivity_Monitor_Threshold is expired. The UE shall start to monitor the E-AGCH subframes in the E-AGCH reception pattern on all configured carriers from the next subframe when the timer is expired.

The HS-SCCH reception pattern is illustrated by Figure 11B. The grey subframes correspond to the HS-SCCH reception pattern HS_SCCH_DRX cycle =4.

Figure 11B: Example for HS-SCCH reception pattern

5.13.2 HS-SCCH orders

The Node B may activate and deactivate the discontinuous downlink reception operation through physical layer commands transmitted on one of the HS-SCCHs in the HS-SCCH set as specified in [9].The activation and deactivation of the discontinuous downlink reception operation is applied by the UE in the same subframe as the HS-SICH subframe which contains the HARQ-ACK corresponding to the order. For multi-carrier E-DCH transmission and multi-carrier HS-DSCH reception, the activation and deactivation of the discontinuous downlink reception operation applies to HS-SCCH and E-AGCH on all carriers, namely, when receiving a DRX activation order on HS-SCCH, the UE shall activate the DRX of HS-SCCH and E-AGCH on all carriers; when receiving a DRX deactivation order on HS-SCCH, the UE shall deactivate the DRX of HS-SCCH and E-AGCH on all carriers.