Method and apparatus for performing communication based on CAPC in NR V2X
Provided are a method for performing wireless communication by a first device, and an apparatus for supporting same. The method may comprise: selecting a first sidelink (SL) channel access priority class (CAPC) from among a plurality of SL CAPCs; selecting a destination related to a logical channel with a highest priority from among one or more logical channels related to the first SL CAPC; generating a medium access control (MAC) protocol data unit (PDU) based on at least one first logical channel related to the destination; transmitting, through a physical sidelink control channel (PSCCH), first sidelink control information (SCI) for scheduling of a physical sidelink shared channel (PSSCH) and second SCI; and transmitting, through the PSSCH, the second SCI including an identifier (ID) related to the destination and the MAC PDU.
1 . A method, comprising:
selecting, by a first device, a first sidelink (SL) channel access priority class (CAPC) from among a plurality of SL CAPCs;
selecting, by the first device, a destination related to a logical channel with a highest priority from among one or more logical channels related to the first SL CAPC;
generating, by the first device, a medium access control (MAC) protocol data unit (PDU) based on at least one first logical channel related to the destination;
transmitting, by the first device, through a physical sidelink control channel (PSCCH), first sidelink control information (SCI) for scheduling of a physical sidelink shared channel (PSSCH) and second SCI;
transmitting, by the first device, through the PSSCH, the second SCI including an identifier (ID) related to the destination and the MAC PDU,
wherein the first SL CAPC is a SL CAPC having a highest priority among the plurality of SL CAPCs; and
selecting, by the first device, a second SL CAPC having a lower priority than the first SL CAPC having the highest priority, based on that the MAC PDU can accommodate additional data.
2 . The method of claim 1 , wherein resources for the MAC PDU are allocated to the at least one first logical channel related to the destination in decreasing priority order.
3 . The method of claim 2 , wherein the resources for the MAC PDU are allocated to the at least one first logical channel related to the destination in order from a logical channel with a high priority to a logical channel with a low priority.
4 . The method of claim 1 , wherein at least one second logical channel of one or more logical channels related to the second SL CAPC is related to the destination.
5 . The method of claim 4 , wherein the MAC PDU is generated based on the at least one first logical channel related to the destination and the at least one second logical channel related to the destination.
6 . The method of claim 4 , wherein resources for the MAC PDU are allocated to the at least one first logical channel related to the destination in decreasing priority order, and then allocated to the at least one second logical channel related to the destination in decreasing priority order.
7 . The method of claim 4 , wherein resources for the MAC PDU are allocated to the at least one first logical channel related to the destination in order from a logical channel with a high priority to a logical channel with a low priority, and then allocated to the at least one second logical channel related to the destination in order from a logical channel with a high priority to a logical channel with a low priority.
8 . The method of claim 4 , wherein, based on that a highest priority of the at least one first logical channel is lower than a highest priority of the at least one second logical channel, resources for the MAC PDU are allocated to the at least one first logical channel in decreasing priority order, and then allocated to the at least one second logical channel in decreasing priority order.
9 . The method of claim 1 , wherein the first SL CAPC is a SL CAPC selected based on a random backoff from among the plurality of SL CAPCs.
10 . The method of claim 9 , wherein resources for the MAC PDU are allocated to the at least one first logical channel related to the destination in decreasing priority order.
11 . The method of claim 10 , wherein the resources for the MAC PDU are allocated to the at least one first logical channel related to the destination in order from a logical channel with a high priority to a logical channel with a low priority.
12 . A 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 by the at least one processor, cause the first device to perform operations comprising:
selecting a first sidelink (SL) channel access priority class (CAPC) from among a plurality of SL CAPCs;
selecting a destination related to a logical channel with a highest priority from among one or more logical channels related to the first SL CAPC;
generating a medium access control (MAC) protocol data unit (PDU) based on at least one first logical channel related to the destination;
transmitting, through a physical sidelink control channel (PSCCH), first sidelink control information (SCI) for scheduling of a physical sidelink shared channel (PSSCH) and second SCI;
transmitting, through the PSSCH, the second SCI including an identifier (ID) related to the destination and the MAC PDU,
wherein the first SL CAPC is a SL CAPC having a highest priority among the plurality of SL CAPCs; and
selecting, by the first device, a second SL CAPC having a lower priority than the first SL CAPC having the highest priority, based on that the MAC PDU can accommodate additional data.
13 . The first device of claim 12 , wherein resources for the MAC PDU are allocated to the at least one first logical channel related to the destination in decreasing priority order.
14 . The first device of claim 13 , wherein the resources for the MAC PDU are allocated to the at least one first logical channel related to the destination in order from a logical channel with a high priority to a logical channel with a low priority.
15 . A 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 by the at least one processor, cause a first device to perform operations comprising:
selecting a first sidelink (SL) channel access priority class (CAPC) from among a plurality of SL CAPCs;
selecting a destination related to a logical channel with a highest priority from among one or more logical channels related to the first SL CAPC;
generating a medium access control (MAC) protocol data unit (PDU) based on at least one first logical channel related to the destination;
transmitting, through a physical sidelink control channel (PSCCH), first sidelink control information (SCI) for scheduling of a physical sidelink shared channel (PSSCH) and second SCI;
transmitting, through the PSSCH, the second SCI including an identifier (ID) related to the destination and the MAC PDU,
wherein the first SL CAPC is a SL CAPC having a highest priority among the plurality of SL CAPCs; and
selecting, by the first device, a second SL CAPC having a lower priority than the first SL CAPC having the highest priority, based on that the MAC PDU can accommodate additional data.
16 . The processing device of claim 15 , wherein resources for the MAC PDU are allocated to the at least one first logical channel related to the destination in decreasing priority order.