Exchanging quasi colocation information between a user equipment and a base station that indicates an association between a spatial parameter and a current transmission configuration

1. A method of operating a user equipment (UE), comprising:

decoding a first downlink control information (DCI) that triggers a first reference signal operation associated with first Quasi Co-Location (QCL) information, wherein the first QCL information indicates an association between a spatial parameter and a current transmission configuration;

attempting to decode a second DCI that triggers a second reference signal operation associated with second QCL information; and

transmitting, to a base station (BS), the first QCL information if the attempt is unsuccessful or the second QCL information if the attempt is successful.

2. The method of claim 1 , wherein the spatial parameter is a spatial domain receive filter for downlink communications or a spatial domain transmit filter for uplink communications.

3. The method of claim 1 , wherein the transmitted QCL information comprises one or more Transmission Configuration Information (TCI) state assumptions.

4. The method of claim 1 , wherein the transmitted QCL information comprises a reference to the most recent message associated with the first or second QCL information that was successfully received at the UE.

5. The method of claim 1 , wherein the transmitted QCL information is associated with one or more reference signals.

6. The method of claim 5 , wherein the one or more reference signals include a data channel reference signal or a control channel reference signal.

7. The method of claim 5 , wherein one of the reference signals is generic to a channel type.

8. The method of claim 5 ,

wherein a first of the reference signals includes a data channel reference signal or a control channel reference signal, and

wherein a second of the reference signals is generic to a channel type.

9. The method of claim 8 , wherein the second reference signal is a Channel State Information (CSI) Reference Signal (RS).

10. The method of claim 1 , further comprising:

receiving, from the BS, a request for the UE to report current QCL information as determined at the UE,

wherein the transmitting is performed in response to the request.

11. The method of claim 1 , wherein the transmitting is performed without an express request from the BS for the UE to report current QCL information as determined at the UE.

12. The method of claim 1 , further comprising:

receiving, from the BS in response to the transmitting, updated QCL information if the transmitted QCL information is not up-to-date.

13. The method of claim 1 , wherein updated QCL information is not received from the BS if the transmitted QCL information is up-to-date.

14. A method of operating a base station (BS), comprising:

transmitting a first downlink control information (DCI) that triggers a first reference signal operation associated with first Quasi Co-Location (QCL) information, wherein the first QCL information indicates an association between a spatial parameter and a current transmission configuration;

transmitting a second DCI that triggers a second reference signal operation associated with second QCL information; and

receiving, from a user equipment (UE), the first QCL information if an attempt by the UE to decode the second DCI is unsuccessful or the second QCL information if the attempt by the UE to decode the second DCI is successful.

15. The method of claim 14 , wherein the spatial parameter is a spatial domain receive filter for downlink communications or a spatial domain transmit filter for uplink communications.

16. The method of claim 14 , wherein the received QCL information comprises one or more Transmission Configuration Information (TCI) state assumptions.

17. The method of claim 14 , wherein the received QCL information comprises a reference to the most recent message associated with the first or second QCL information that was successfully received at the UE.

18. The method of claim 14 , wherein the received QCL information is associated with one or more reference signals.

19. The method of claim 18 , wherein one of the reference signals includes a data channel reference signal or a control channel reference signal.

20. The method of claim 18 , wherein one of the reference signals is generic to a channel type.

21. The method of claim 18 ,

wherein a first of the reference signals includes a data channel reference signal or a control channel reference signal, and

wherein a second of the reference signals is generic to a channel type.

22. The method of claim 18 , wherein the second reference signal is a Channel State Information (CSI) Reference Signal (RS).

23. The method of claim 14 , further comprising:

determining whether the received QCL information received from the UE is up-to-date; and

selectively transmitting up-to-date QCL information to the UE based on the determining.

24. The method of claim 14 , further comprising:

transmitting, to the UE, a request for the UE to report current QCL information as determined at the UE,

wherein the receiving occurs in response to the request.

25. The method of claim 14 , wherein the receiving occurs without an express request from the BS for the UE to report current QCL information as determined at the UE.

26. The method of claim 14 , wherein the received QCL information includes:

Transmission Configuration Information (TCI) state assumptions, or

a reference to the most recent message associated with the first or second QCL information that was successfully received at the UE, or

a combination thereof.

27. A user equipment (UE), comprising:

means for decoding a first downlink control information (DCI) that triggers a first reference signal operation associated with first Quasi Co-Location (QCL) information, wherein the first QCL information indicates an association between a spatial parameter and a current transmission configuration;

means for attempting to decode a second DCI that triggers a second reference signal operation associated with second QCL information; and

and

means for transmitting, to a base station (BS), the first QCL information if the attempt is unsuccessful or the second QCL information if the attempt is successful.

28. The UE of claim 27 , wherein the spatial parameter is a spatial domain receive filter for downlink communications or a spatial domain transmit filter for uplink communications.

29. The UE of claim 27 , wherein the transmitted QCL information comprises one or more Transmission Configuration Information (TCI) state assumptions.

30. The UE of claim 27 , wherein the transmitted QCL information comprises a reference to the most recent message associated with the first or second QCL information that was successfully received at the UE.

31. A base station (BS), comprising:

a memory;

at least one processor; and

means for transmitting a first downlink control information (DCI) that triggers a first reference signal operation associated with first Quasi Co-Location (QCL) information, wherein the first QCL information indicates an association between a spatial parameter and a current transmission configuration;

means for transmitting a second DCI that triggers a second reference signal operation associated with second QCL information; and

means for receiving, from a user equipment (UE), the first QCL information if an attempt by the UE to decode the second DCI is unsuccessful or the second QCL information if the attempt by the UE to decode the second DCI is successful.

32. The BS of claim 31 , wherein the spatial parameter is a spatial domain receive filter for downlink communications or a spatial domain transmit filter for uplink communications.

33. The BS of claim 31 , wherein the received QCL information comprises one or more Transmission Configuration Information (TCI) state assumptions.

34. The BS of claim 31 , wherein the received QCL information comprises a reference to the most recent message associated with the first or second QCL information that was successfully received at the UE.

35. A user equipment (UE), comprising:

a memory; and

at least one processor coupled to the memory and configured to:

decode a first downlink control information (DCI) that triggers a first reference signal operation associated with first Quasi Co-Location (QCL) information, wherein the first QCL information indicates an association between a spatial parameter and a current transmission configuration;

attempt to decode a second DCI that triggers a second reference signal operation associated with second QCL information; and

transmit, to a base station (BS), the first QCL information if the attempt is unsuccessful or the second QCL information if the attempt is successful.

36. The UE of claim 35 , wherein the spatial parameter is a spatial domain receive filter for downlink communications or a spatial domain transmit filter for uplink communications.

37. The UE of claim 35 , wherein the transmitted QCL information comprises one or more Transmission Configuration Information (TCI) state assumptions.

38. The UE of claim 35 , wherein the transmitted QCL information comprises a reference to the most recent message associated with the first or second QCL information that was successfully received at the UE.

39. A base station (BS), comprising:

a memory; and

at least one processor coupled to the memory and configured to:

transmit a first downlink control information (DCI) that triggers a first reference signal operation associated with first Quasi Co-Location (QCL) information, wherein the first QCL information indicates an association between a spatial parameter and a current transmission configuration;

transmit a second DCI that triggers a second reference signal operation associated with second QCL information; and

receive, from a user equipment (UE), the first QCL information if an attempt by the UE to decode the second DCI is unsuccessful or the second QCL information if the attempt by the UE to decode the second DCI is successful.

40. The BS of claim 39 , wherein the spatial parameter is a spatial domain receive filter for downlink communications or a spatial domain transmit filter for uplink communications.

41. The BS of claim 39 , wherein the received QCL information comprises one or more Transmission Configuration Information (TCI) state assumptions.

42. The BS of claim 39 , wherein the received QCL information comprises a reference to the most recent message associated with the first or second QCL information that was successfully received at the UE.

43. A non-transitory computer-readable medium containing instructions stored thereon, which, when executed by a user equipment (UE), cause the UE to perform operations, the instructions comprising:

at least one instruction to cause the UE to decode a first downlink control information (DCI) that triggers a first reference signal operation associated with first Quasi Co-Location (QCL) information, wherein the first QCL information indicates an association between a spatial parameter and a current transmission configuration;

at least one instruction to cause the UE to attempt to decode a second DCI that triggers a second reference signal operation associated with second QCL information; and

at least one instruction to cause the UE to transmit, to a base station (BS), the first QCL information if the attempt is unsuccessful or the second QCL information if the attempt is successful.

44. A non-transitory computer-readable medium containing instructions stored thereon, which, when executed by a base station (BS), cause the BS to perform operations, the instructions comprising:

at least one instruction to cause the BS to transmit a first downlink control information (DCI) that triggers a first reference signal operation associated with first Quasi Co-Location (QCL) information, wherein the first QCL information indicates an association between a spatial parameter and a current transmission configuration;

at least one instruction to cause the BS to transmit a second DCI that triggers a second reference signal operation associated with second QCL information; and

at least one instruction to cause the BS to receive, from a user equipment (UE), the first QCL information if an attempt by the UE to decode the second DCI is unsuccessful or the second QCL information if the attempt by the UE to decode the second DCI is successful.