Sidelink resource allocation and MAC reset

A wireless device configured to operate in a wireless communication system, the wireless device comprising:

• at least one transceiver;
• at least one processor;
• and
• at least one memory operably connectable to the at least one processor and storing instructions that, based on being executed by the at least one processor, perform operations comprising:
• establishing a radio resource control (RRC) connection with a base station;
• based on the wireless device being configured with a sidelink resource allocation mode 1, receiving, from the base station via the at least one transceiver, a physical downlink control channel (PDCCH) based on a sidelink radio network temporary identity (SL-RNTI), wherein the PDCCH includes i) a sidelink grant, and ii) a new data indicator (NDI) for a hybrid automatic repeat request (HARQ) process identifier (ID) related to the sidelink grant;
• associating a sidelink process related to a transport block (TB) to the sidelink grant;
• associating the HARQ process ID to the sidelink process;
• performing, via the at least one transceiver, transmission of the TB based on the sidelink grant;
• and
• based on a media access control (MAC) reset being requested by an upper layer of the wireless device, setting NDIs for all HARQ process IDs to value 0 for receiving a PDCCH based on the SL-RNTI,
• wherein the all HARQ process IDs include the HARQ process ID.

A processing apparatus configured to control a wireless device in a wireless communication system, the processing apparatus comprising:

• at least one processor;
• and
• at least one memory operably connectable to the at least one processor, wherein the at least one processor is configured to perform operations comprising:
• based on the wireless device being configured with a sidelink resource allocation mode 1, obtaining, via a physical downlink control channel (PDCCH) based on a sidelink radio network temporary identity (SL-RNTI), i) a sidelink grant, and ii) a new data indicator (NDI) for a hybrid automatic repeat request (HARQ) process identifier (ID) related to the sidelink grant;
• associating a sidelink process related to a transport block (TB) to the sidelink grant;
• associating the HARQ process ID to the sidelink process;
• and
• based on a media access control (MAC) reset being requested by an upper layer, setting NDIs for all HARQ process IDs to value 0 for receiving a PDCCH based on the SL-RNTI,
• wherein the all HARQ process IDs include the HARQ process ID.