Method and device for performing RLM in NR V2X
Provided are a method for a first device to perform wireless communication, and a device supporting same. The method may comprise: a step for receiving, from a second device, a plurality of reference signals or N SCIs through N channels; a step for determining, on the basis of at least one among the sequence of the plurality of reference signals and the N SCIs, the number or ratio of channels that have failed in reception; and a step for performing radio link monitoring (RLM) on the basis of the number or ratio of channels that have failed in reception. N may be a positive integer.
1. A method performed by a first device in a wireless communication system, the method comprising:
obtaining information related to a threshold number for radio link failure (RLF) detection;
transmitting, to a second device, first sidelink control information (SCI) on a physical sidelink control channel (PSCCH), for scheduling a physical sidelink shared channel (PSSCH) and second SCI on the PSSCH;
transmitting, to the second device, the second SCI on the PSSCH;
incrementing a number for the RLF detection by 1 based on that a hybrid automatic repeat request (HARQ) feedback for the PSSCH is absent; and
detecting RLF based on that the number for the RLF detection reaches the threshold number for the RLF detection.
2. The method of claim 1 , wherein the PSSCH includes at least one of a CSI-RS or pre-configured dummy information.
3. The method of claim 1 , wherein the threshold number for the RLF detection is obtained based on receiving the threshold number for the RLF detection from the base station.
4. The method of claim 1 , wherein the threshold number for the RLF detection is obtained based on pre-configuration by the first device.
5. The method of claim 1 , wherein the RLF detection is for a unicast transmission.
6. The method of claim 1 , wherein the RLF detection is indicated to radio resource control (RRC).
7. The method of claim 1 , wherein the RLF detection is hybrid automatic repeat request (HARQ)-based RLF detection.
8. The method of claim 1 , wherein the RLF detection is for a PC5-RRC connection.
9. The method of claim 8 , wherein the PC5-RRC connection is established by upper layers.
10. The method of claim 8 , wherein the number for the RLF detection is maintained for the PC5-RRC connection.
11. The method of claim 8 , wherein, based upon establishment of the PC5-RRC connection, the number for the RLF detection is initialized to zero.
12. The method of claim 8 , wherein, based upon establishment of the PC5-RRC connection, the number for the RLF detection is re-initialized to zero.
13. The method of claim 8 , wherein, based upon configuration or reconfiguration of the threshold number for the RLF detection, the number for the RLF detection is initialized to zero.
14. The method of claim 8 , wherein, based upon configuration or reconfiguration of the threshold number for the RLF detection, the number for the RLF detection is re-initialized to zero.
15. The method of claim 8 , wherein, based on the HARQ feedback for the PSSCH is present, the number for the RLF detection is re-initialized to zero.
16. The method of claim 1 , wherein the RLF detection is a sidelink RLF detection.
17. The method of claim 1 , wherein the number for the RLF detection is a number of consecutive discontinuous transmission (DTX).
18. 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:
obtaining information related to a threshold number for radio link failure (RLF) detection;
transmitting, to a second device, first sidelink control information (SCI) on a physical sidelink control channel (PSCCH), for scheduling a physical sidelink shared channel (PSSCH) and second SCI on the PSSCH;
transmitting, to the second device, the second SCI on the PSSCH;
incrementing a number for the RLF detection by 1 based on that a hybrid automatic repeat request (HARQ) feedback for the PSSCH is absent; and
detecting RLF based on that the number for the RLF detection reaches the threshold number for the RLF detection.
19. A processing device adapted to control a first device, the first 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 first device to perform operations comprising:
obtaining information related to a threshold number for radio link failure (RLF) detection;
transmitting, to a second device, first sidelink control information (SCI) on a physical sidelink control channel (PSCCH), for scheduling a physical sidelink shared channel (PSSCH) and second SCI on the PSSCH;
transmitting, to the second device, the second SCI on the PSSCH;
incrementing a number for the RLF detection by 1 based on that a hybrid automatic repeat request (HARQ) feedback for the PSSCH is absent; and
detecting RLF based on that the number for the RLF detection reaches the threshold number for the RLF detection.