User equipment and method for activating PUCCH spatial relation

1. A user equipment (UE), comprising:

at least one processor; and

at least one memory coupled to the at least one processor and storing computer-executable instructions that when executed by the at least one processor, cause the UE to:

receive, from a base station (BS), a medium access control (MAC) control element (CE) comprising at least a first field and a second field, the first field indicating an identifier (ID) of a specific physical uplink control channel (PUCCH) spatial relation to be activated or deactivated, and the second field indicating an ID of a specific PUCCH resource;

apply the MAC CE to all PUCCH resources in a specific PUCCH group that includes the specific PUCCH resource in a case that the MAC CE is identified by a first logical channel ID (LCID); and

apply the MAC CE to the specific PUCCH resource in a case that the MAC CE is identified by a second LCID.

2. The UE of claim 1 , wherein the computer-executable instructions, when executed by the at least one processor, further cause the processor UE to:

receive, from the BS, a radio resource control (RRC) message to configure a plurality of PUCCH groups, each of the plurality of PUCCH groups including a plurality of PUCCH resources.

3. The UE of claim 2 , wherein the MAC CE does not include an ID of any of the configured plurality of PUCCH groups.

4. The UE of claim 1 , wherein the computer-executable instructions, when executed by the at least one processor, further cause the UE to:

receive, from the BS, a radio resource control (RRC) message to configure a plurality of PUCCH spatial relations.

5. The UE of claim 4 , wherein the computer-executable instructions, when executed by the at least one processor, further cause the UE to:

obtain an updated list of the configured plurality of PUCCH spatial relations by merging PUCCH spatial relations that correspond to a same receiving beam; and

transmit the updated list to the BS.

6. The UE of claim 4 , wherein the computer-executable instructions, when executed by the at least one processor, further cause the UE to:

transmit, to the BS, information related to a receiving beam that corresponds to each of the configured plurality of PUCCH spatial relations.

7. The UE of claim 1 , wherein the first field is a bitmap corresponding to the specific PUCCH spatial relation.

8. The UE of claim 1 , wherein the MAC CE further comprises a third field indicating whether the specific PUCCH spatial relation is activated for all PUCCH resources configured by the BS.

9. The UE of claim 1 , wherein the MAC CE further comprises:

a third field indicating an identity of a single PUCCH resource; and

a fourth field indicating that the specific PUCCH spatial relation is activated for the single PUCCH resource or for the specific PUCCH resource.

10. The UE of claim 1 , wherein the MAC CE further comprises a third field indicating that the specific PUCCH spatial relation is to be deactivated.

11. A method performed by a user equipment (UE) for activating a physical uplink control channel (PUCCH) spatial relation, the method comprising:

receiving, from a base station (BS), a medium access control (MAC) control element (CE) comprising at least a first field and a second field, the first field indicating an identifier (ID) of a specific PUCCH spatial relation to be activated or deactivated, and the second field indicating an ID of a specific PUCCH resource;

applying the MAC CE to all PUCCH resources in a specific PUCCH group that includes the specific PUCCH resource in a case that the MAC CE is identified by a first logical channel ID (LCID); and

applying the MAC CE to the specific PUCCH resource in a case that the MAC CE is identified by a second LCID.

12. The method of claim 11 , further comprising:

receiving, from the BS, a radio resource control (RRC) message to configure a plurality of PUCCH groups, each of the plurality of PUCCH groups including a plurality of PUCCH resources.

13. The method of claim 12 , wherein the MAC CE does not include an ID of any of the configured plurality of PUCCH groups.

14. The method of claim 11 , further comprising:

receiving, from the BS, a radio resource control (RRC) message to configure a plurality of PUCCH spatial relations.

15. The method of claim 14 , further comprising:

obtaining an updated list of the configured plurality of PUCCH spatial relations by merging PUCCH spatial relations that correspond to a same receiving beam; and

transmitting the updated list to the BS.

16. The method of claim 14 , further comprising:

transmitting, to the BS, information related to a receiving beam that corresponds to each of the configured plurality of PUCCH spatial relations.

17. The method of claim 11 , wherein the first field is a bitmap corresponding to the specific PUCCH spatial relation.

18. The method of claim 11 , wherein the MAC CE further comprises a third field indicating whether the specific PUCCH spatial relation is activated for all PUCCH resources configured by the BS.

19. The method of claim 11 , wherein the MAC CE further comprises:

a third field indicating an identity of a single PUCCH resource; and

a fourth field indicating that the specific PUCCH spatial relation is activated for the single PUCCH resource or for the specific PUCCH resource.

20. The method of claim 11 , wherein the MAC CE further comprises a third field indicating that the specific PUCCH spatial relation is to be deactivated.