Drx harq rtt timer operation method and device for supporting mode 1 upon occurrence of lbt failure in nr-u

A first device adapted to perform wireless communication, the first device comprising:

• at least one transceiver;
• at least one processor;
• and
• at least one memory connected to the at least one processor and storing instructions that, based on being executed, cause the first device to perform operations comprising:
• receiving, from a base station, information related to a first sidelink (SL) resource and information related to physical uplink control channel (PUCCH) resource for reporting hybrid automatic repeat request (HARQ) feedback for SL transmission to the base station;
• obtaining a discontinuous reception (DRX) configuration including at least one of DRX HARQ round trip time (RTT) timer or DRX retransmission timer;
• performing the SL transmission based on the first SL resource;
• generating the HARQ feedback for the SL transmission;
• performing a listen before talk (LBT) for PUCCH transmission;
• and
• determining whether to start the DRX HARQ RTT timer, based on (i) the HARQ feedback and (ii) a failure of transmission of the HARQ feedback to the base station due to a failure of the LBT.

A processing device adapted to control a first device to perform wireless communication, the processing device comprising:

• at least one processor;
• and
• at least one memory connected to the at least one processor and storing instructions that, based on being executed, cause the at least one processor to perform operations comprising:
• receiving, from a base station, information related to a first sidelink (SL) resource and information related to physical uplink control channel (PUCCH) resource for reporting hybrid automatic repeat request (HARQ) feedback for SL transmission to the base station;
• obtaining a discontinuous reception (DRX) configuration including at least one of DRX HARQ round trip time (RTT) timer or DRX retransmission timer;
• performing the SL transmission based on the first SL resource;
• generating the HARQ feedback for the SL transmission;
• performing a listen before talk (LBT) for PUCCH transmission;
• and
• determining whether to start the DRX HARQ RTT timer, based on (i) the HARQ feedback and (ii) a failure of transmission of the HARQ feedback to the base station due to a failure of the LBT.