Multi-beam operation with a single TCI state

1. A method for wireless communication by a user equipment (UE), the method comprising:

receiving a single transmission configuration indicator (TCI) state from a base station (BS);

determining two or more UE receive beams based, at least in part, on the received single TCI state; and

receiving a multi-beam data transmission from the BS using the determined two or more UE receive beams.

2. The method of claim 1 , further comprising performing one or more beam management procedures including:

measuring a plurality of repetitions of a reference signal (RS) from the BS using a plurality of UE receive beams, each of the repetitions transmitted via a first set of a plurality of BS transmit beams; and

determining one or more preferred UE receive beams, of the plurality of UE receive beams, based on the measured plurality of repetitions.

3. The method of claim 2 , wherein the performing the one or more beam management procedures further includes:

measuring another RS from the BS using the one or more preferred UE receive beams, the other RS associated with the first set of BS transmit beams; and

reporting channel state information (CSI) to the BS based on the measurement, and wherein:

the CSI includes at least precoding matrix indicator (PMI) feedback;

the single TCI state indicates the other RS; and

the determining the two or more UE receive beams based, at least in part, on the single TCI state comprises determining the one or more preferred UE receive beams associated with the other RS indicated by the single TCI state.

4. The method of claim 3 , wherein the reporting the CSI to the BS comprises reporting the CSI for only a subset of the first set of BS transmit beams.

5. The method of claim 3 , wherein the determining the two or more UE receive beams based, at least in part, on the single TCI state includes:

determining analog detecting based on the one or more preferred UE receive beams associated with the single TCI state;

determining digital detecting based on one or more demodulation reference signals (DMRS) associated with the multi-beam data transmission; and

determining one or more hybrid detecting UE receive beams based on the analog detecting and the digital detecting.

6. The method of claim 2 , wherein the determining the one or more preferred UE receive beams comprises selecting one or more UE receive beams from a predefined beam codebook or generating one or more UE receive beams without using a predefined beam codebook.

7. The method of claim 2 , wherein the performing the one or more beam management procedures further includes:

measuring a plurality of RSs from the BS, each of the RSs associated with a different BS transmit beam; and

determining a plurality of preferred BS transmit beams based on the measurements, and wherein the first set of BS transmit beams comprises the plurality of preferred BS transmit beams.

8. The method of claim 2 , further comprising receiving a channel state information (CSI) configuration for the one or more beam management procedures, the CSI configuration configuring the UE with at least one CSI reference signal (CSI-RS) resource set, each CSI-RS resource set including one or more CSI-RS resources comprising a number of available ports, wherein the RS from the BS comprises CSI-RS, and wherein the measuring the plurality of repetitions of the RS comprises measuring each CSI-RS using the CSI-RS resources in a CSI-RS resource set.

9. The method of claim 8 , wherein the CSI configuration configures CSI-RS for a type-II port selection codebook.

10. The method of claim 9 , wherein the UE is restricted to selecting only adjacent beams.

11. The method of claim 8 , wherein at least one CSI-RS resource comprises a plurality of ports, each port associated with a different BS transmit beam for CSI-RS.

12. The method of claim 8 , wherein at least one of the CSI-RS resource sets comprises a plurality of CSI-RS resources.

13. The method of claim 8 , wherein, for each of the CSI-RS resource sets, the CSI configuration indicates whether CSI-RS repetition is configured.

14. A method for wireless communication by a base station (BS), the method comprising:

determining multiple transmit beams to use for sending a multi-beam data transmission;

sending, to a user equipment (UE), a single transmission configuration indicator (TCI) state to indicate the multiple transmit beams; and

sending the multi-beam data transmission to the UE based on the single TCI state.

15. The method of claim 14 , further comprising performing one or more beam management procedures with the UE including sending a plurality of repetitions of a reference signal (RS) to the UE, each repetition transmitted using a first set of BS transmit beams.

16. The method of claim 15 , wherein the performing the one or more beam management procedures with the UE further includes:

sending another RS to the UE using the first set of BS transmit beams, wherein the TCI indicates the other RS; and

receiving channel state information (CSI) from the UE, and wherein the CSI includes at least a precoding matrix indicator (PMI) feedback.

17. The method of claim 16 , wherein the CSI comprises CSI for only a subset of the first set of BS transmit beams.

18. The method of claim 16 , further comprising determining a plurality of BS transmit beams to use for the multi-beam data transmission to the UE based, at least in part, on the PMI feedback.

19. The method of claim 18 , wherein the determining the plurality of BS transmit beams to use for the multi-beam data transmission to the UE comprises:

determining analog precoding based on the first set of BS transmit beams;

determining digital precoding based on the PMI feedback; and

determining one or more hybrid beamforming BS transmit beams based on the analog precoding and the digital precoding.

20. The method of claim 15 , wherein the performing the one or more beam management procedures with the UE further includes:

sending a plurality of RSs to the UE, each of the RSs associated with a different BS transmit beam; and

receiving an indication from the UE of a plurality of preferred BS transmit beams, and wherein the first set of BS transmit beams comprises the plurality of preferred BS transmit beams.

21. The method of claim 15 , further comprising sending the UE a channel state information (CSI) configuration for the one or more beam management procedures, the CSI configuration configuring the UE with at least one CSI reference signal (CSI-RS) resource set, each CSI-RS resource set including one or more CSI resources comprising a number of available ports, wherein the RS comprises CSI-RS.

22. The method of claim 21 , wherein the CSI configuration configures CSI-RS for a type-II port selection codebook.

23. The method of claim 21 , wherein at least one CSI-RS resource comprises a plurality of ports, each port associated with a different BS transmit beam for CSI-RS.

24. The method of claim 21 , wherein at least one of the CSI-RS resource sets comprises a plurality of CSI-RS resources.

25. The method of claim 21 , wherein, for each of the CSI-RS resource sets, the CSI configuration indicates whether CSI-RS repetition is configured.

26. An apparatus for wireless communication, the apparatus comprising:

a memory; and

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

receive a single transmission configuration indicator (TCI) state from another apparatus;

determine two or more receive beams of the apparatus based, at least in part, on the single TCI state; and

receive a multi-beam data transmission from the other apparatus using the determined two or more receive beams.

27. The apparatus of claim 26 , wherein the memory and processor are further configured to perform one or more beam management procedures including:

measuring a plurality of repetitions of a reference signal (RS) from the other apparatus using a plurality of receive beams, each of the repetitions transmitted via a first set of a plurality of transmit beams; and

determining one or more preferred receive beams, of the plurality of receive beams, based on the measured plurality of repetitions.

28. The apparatus of claim 27 , wherein the memory and processor being configured to perform the one or more beam management procedures comprise the memory and processor being configured to:

measure another RS from the other apparatus using the one or more preferred receive beams, the other RS associated with the first set of transmit beams; and

report channel state information (CSI) to the other apparatus based on the measurement, and wherein:

the CSI includes at least precoding matrix indicator (PMI) feedback;

the single TCI state indicates the other RS; and

the determining the one or more receive beams based, at least in part, on the single TCI state comprises determining the one or more preferred receive beams associated with the another RS indicated by the single TCI state.

29. The apparatus of claim 28 , wherein the memory and processor being configured to determine the two or more UE receive beams based, at least in part, on the single TCI state comprises the memory and processor being configured to:

determine analog detecting based on the one or more preferred receive beams associated with the single TCI state;

determine digital detecting based on one or more demodulation reference signals (DMRS) associated with the multi-beam data transmission; and

determine one or more hybrid detecting UE receive beams based on the analog detecting and the digital detecting.

30. The apparatus of claim 27 , wherein the memory and processor being configured to perform the one or more beam management procedures comprise the memory and processor being configured to:

measure a plurality of RSs from the other apparatus, each of the RSs associated with a different transmit beam; and

determine a plurality of preferred transmit beams based on the measurements, and wherein the first set of transmit beams comprises the plurality of preferred transmit beams.

31. The apparatus of claim 27 , wherein the memory and processor being configured to determine the one or more preferred receive beams comprises the memory and processor being configured to: select one or more UE receive beams from a predefined beam codebook or generate one or more UE receive beams without using a predefined beam codebook.

32. The apparatus of claim 27 , wherein the memory and processor configured to perform the one or more beam management procedures comprise the memory and processor configured to:

measure a plurality of RSs from the BS, each of the RSs associated with a different BS transmit beam; and

determine a plurality of preferred BS transmit beams based on the measurements, and wherein the first set of BS transmit beams comprises the plurality of preferred BS transmit beams.

33. The apparatus of claim 27 , wherein the memory and processor are further configured to:

receive a channel state information (CSI) configuration for the one or more beam management procedures, the CSI configuration configuring the UE with at least one CSI reference signal (CSI-RS) resource set, each CSI-RS resource set including one or more CSI-RS resources comprising a number of available ports, wherein the RS from the BS comprises CSI-RS, and

wherein the memory and processor configured to measure the plurality of repetitions of the RS comprise the memory and processor configured to measure each CSI-RS using the CSI-RS resources in a CSI-RS resource set.

34. The apparatus of claim 33 , wherein the CSI configuration configures CSI-RS for a type-II port selection codebook.

35. The apparatus of claim 34 , wherein the UE is restricted to selecting only adjacent beams.

36. The apparatus of claim 33 , wherein at least one CSI-RS resource comprises a plurality of ports, each port associated with a different BS transmit beam for CSI-RS.

37. The apparatus of claim 33 , wherein at least one of the CSI-RS resource sets comprises a plurality of CSI-RS resources.

38. The apparatus of claim 33 , wherein, for each of the CSI-RS resource sets, the CSI configuration indicates whether CSI-RS repetition is configured.

39. An apparatus for wireless communication, the apparatus comprising:

a memory; and

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

determine multiple transmit beams to use for sending a multi-beam data transmission;

send a single transmission configuration indicator (TCI) state to another apparatus to indicate the multiple transmit beams; and

send a multi-beam data transmission to the other apparatus based on the single TCI state.

40. An apparatus for wireless communications, the apparatus comprising:

means for receiving a single transmission configuration indicator (TCI) state from a base station (BS);

means for determining two or more user equipment (UE) receive beams based, at least in part, on the received single TCI state; and

means for receiving a multi-beam data transmission from the BS using the determined two or more UE receive beams.

41. An apparatus for wireless communications, the apparatus comprising:

means for determining multiple transmit beams to use for sending a multi-beam data transmission;

means for sending, to a user equipment (UE), a single transmission configuration indicator (TCI) state to indicate the multiple transmit beams; and

means for sending the multi-beam data transmission to the UE based on the single TCI state.

42. A non-transitory computer readable medium storing computer executable instructions in a memory accessible to a processor for wireless communication by a user equipment (UE), the instructions comprising:

code for receiving a single transmission configuration indicator (TCI) state from a base station (BS);

code for determining two or more UE receive beams based, at least in part, on the received single TCI state; and

code for receiving a multi-beam data transmission from the BS using the determined two or more UE receive beams.

43. The non-transitory computer readable medium of claim 42 , further comprising code for performing one or more beam management procedures, the one or more beam management procedures including:

measuring a plurality of repetitions of a reference signal (RS) from the BS using a plurality of UE receive beams, each of the repetitions transmitted via a first set of a plurality of BS transmit beams; and

determining one or more preferred UE receive beams, of the plurality of UE receive beams, based on the measured plurality of repetitions.

44. The non-transitory computer readable medium of claim 43 , wherein the code for performing the one or more beam management procedures further includes:

measuring another RS from the BS using the one or more preferred UE receive beams, the other RS associated with the first set of BS transmit beams; and

reporting channel state information (CSI) to the BS based on the measurement, and wherein:

the CSI includes at least precoding matrix indicator (PMI) feedback;

the single TCI state indicates the other RS; and

the determining the two or more UE receive beams based, at least in part, on the single TCI state comprises determining the one or more preferred UE receive beams associated with the other RS indicated by the single TCI state.

45. A non-transitory computer readable medium storing computer executable instructions in a memory accessible to a processor for wireless communication by a base station (BS), the instructions comprising:

code for determining multiple transmit beams to use for sending a multi-beam data transmission;

code for sending, to a user equipment (UE), a single transmission configuration indicator (TCI) state to indicate the multiple transmit beams; and

code for sending the multi-beam data transmission to the UE based on the single TCI state.