Method and apparatus for receiving multicast data based on DRX operations in wireless communication system

A user equipment (UE) comprising:

• at least one processor;
• and
• at least one computer memory storing instructions that, when executed by the at least one processor, cause the UE to perform operations comprising:
• receiving a data unit during an active time of a first discontinuous reception (DRX) configuration related to a multicast transmission for a Hybrid Automatic Repeat and request (HARQ) process;
• transmitting a negative response to the network based on the data unit being not successfully decoded;
• starting a HARQ Round-trip Time (RTT) timer of a second DRX configuration related to a unicast transmission for the HARQ process;
• and
• monitoring a physical downlink control channel (PDCCH) related to a retransmitted data unit during an active time of the second DRX configuration,
• wherein the active time of the second DRX configuration comprises a time duration during which a DRX retransmission timer of the second DRX configuration is running after expiry of the HARQ RTT timer.

An apparatus for a user equipment (UE), the apparatus comprising:

• at least one processor;
• and
• at least one computer memory storing instructions that, when executed by the at least one processor, cause the UE to perform operations comprising:
• receiving a data unit during an active time of a first discontinuous reception (DRX) configuration related to a multicast transmission for a Hybrid Automatic Repeat and request (HARQ) process;
• transmitting a negative response to the network based on the data unit being not successfully decoded;
• starting a HARQ Round-trip Time (RTT) timer of a second DRX configuration related to a unicast transmission for the HARQ process;
• and
• monitoring a physical downlink control channel (PDCCH) related to a retransmitted data unit during an active time of the second DRX configuration,
• wherein the active time of the second DRX configuration comprises a time duration during which a DRX retransmission timer of the second DRX configuration is running after expiry of the HARQ RTT timer.

A non-transitory computer readable storage medium comprising program instructions that, when executed by at least one processor, cause a user equipment (UE) to perform operations comprising:

• receiving a data unit during an active time of a first discontinuous reception (DRX) configuration related to a multicast transmission for a Hybrid Automatic Repeat and request (HARQ) process;
• transmitting a negative response to the network based on the data unit being not successfully decoded;
• starting a HARQ Round-trip Time (RTT) timer of a second DRX configuration related to a unicast transmission for the HARQ process;
• and
• monitoring a physical downlink control channel (PDCCH) related to a retransmitted data unit during an active time of the second DRX configuration,
• wherein the active time of the second DRX configuration comprises a time duration during which a DRX retransmission timer of the second DRX configuration is running after expiry of the HARQ RTT timer.