Handover mechanism for non-terrestrial network (NTN) system in 5G new radio (NR)

1. A method for wireless communication, the method comprising:

initiating, by a user equipment (UE), a registration process with a network entity of a non-terrestrial network (NTN) to access the NTN; and

transmitting, by the UE to the network entity, UE capability information of the UE, the UE capability information indicating a steering type comprising a mechanical steering or an electronic steering.

2. The method of claim 1 , wherein the UE capability information is transmitted during the registration process.

3. The method of claim 1 , wherein the UE capability information indicates a handover delay corresponding to the UE.

4. The method of claim 3 , wherein the handover delay comprises an intra-satellite handover delay, an inter-satellite handover delay, or a combination thereof.

5. The method of claim 4 , wherein the intra-satellite handover delay corresponds to an antenna repointing delay of the UE.

6. The method of claim 5 , wherein the inter-satellite handover delay corresponds to the antenna repointing delay and a communication delay associated with an exchange of control signaling between a first platform of the NTN and a second platform of the NTN.

7. The method of claim 1 , further comprising transmitting, by the UE to the network entity, location data indicating a location of the UE.

8. The method of claim 7 , wherein the location data is transmitted during the registration process or after the registration process.

9. The method of claim 7 , wherein the location data is transmitted responsive to a request from the network entity.

10. The method of claim 1 , further comprising transmitting, by the UE to the network entity, mobility information of the UE.

11. The method of claim 10 , wherein the mobility information comprises speed information of the UE, a travel path of the UE, or a combination thereof.

12. The method of claim 10 , wherein the mobility information is transmitted during the registration process or after the registration process.

13. The method of claim 10 , wherein the mobility information is transmitted responsive to a request from the network entity.

14. The method of claim 1 , further comprising:

receiving, by the UE from the network entity, a handover command; and

wherein the handover command comprising a handover time indicator associated with a target handover time for the UE to perform a handover operation from a first beam to a second beam.

15. The method of claim 14 , wherein the target handover time is determined independent of a measurement report from the UE.

16. The method of claim 15 , wherein the measurement report corresponds to the second beam.

17. The method of claim 14 , wherein the first beam corresponds to a first platform and the second beam corresponds to the first platform or a second platform.

18. The method of claim 14 , wherein the handover operation comprises an intra-satellite handover or an inter-satellite handover.

19. The method of claim 14 , wherein the target handover time is determined based on UE capability information, location data, mobility information, a model associated with a flight path of one or more platforms, or a combination thereof.

20. The method of claim 14 , further comprising performing, by the UE, the handover operation with the network entity.

21. The method of claim 1 , further comprising receiving, by the UE, a request for a measurement report from the network entity.

22. The method of claim 21 , further comprising:

transmitting, by the UE, the measurement report; and

wherein the measurement report corresponds to a second beam.

23. The method of claim 21 , wherein the measurement report is transmitted after performance of a handover operation by the UE to change from a first beam to a second beam.

24. The method of claim 21 , further comprising:

measuring, by the UE, a downlink signal strength of a second beam, a downlink signal quality of the second beam, or a combination thereof; and

wherein the measurement report indicates the downlink signal strength of the second beam, the downlink signal quality of the second beam, or a combination thereof.

25. The method of claim 1 , further comprising:

receiving, by the UE, a radio resource control (RRC) configuration message from the network entity; and

wherein the RRC configuration message includes a handover time indicator, an identifier of the UE, a first indication of a first beam, a second indication of a second beam, an indicator to request a measurement report from the UE, or a combination thereof.

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

at least one processor; and

a memory coupled to the at least one processor,

wherein the at least one processor is configured to:

initiate, by a user equipment (UE), a registration process with a network entity of a non-terrestrial network (NTN) to access the NTN; and

transmit, by the UE to the network entity, UE capability information of the UE, the UE capability information indicating a steering type comprising a mechanical steering or an electronic steering.

27. The apparatus of claim 26 , wherein:

the UE capability information is transmitted during the registration process.

28. The apparatus of claim 26 , wherein:

the UE capability information indicates:

a handover delay corresponding to the UE.

29. The apparatus of claim 28 , wherein:

the handover delay comprises an intra-satellite handover delay, an inter-satellite handover delay, or a combination thereof.

30. The apparatus of claim 29 , wherein:

the inter-satellite handover delay corresponds to the antenna repointing delay and a communication delay associated with an exchange of control signaling between a first platform of the NTN and a second platform of the NTN.

31. The apparatus of claim 26 , wherein the at least one processor is further configured to:

transmit, by the UE to the network entity, location data indicating a location of the UE.

32. The apparatus of claim 31 , wherein:

the location data is transmitted during the registration process or after the registration process.

33. The apparatus of claim 31 , wherein:

the location data is transmitted responsive to a request from the network entity.

34. The apparatus of claim 26 , wherein the at least one processor is further configured to:

transmit, by the UE to the network entity, mobility information of the UE.

35. The apparatus of claim 34 , wherein:

the mobility information comprises speed information of the UE, a travel path of the UE, or a combination thereof.

36. The apparatus of claim 34 , wherein:

the mobility information is transmitted during the registration process or after the registration process.

37. The apparatus of claim 34 , wherein:

the mobility information is transmitted responsive to a request from the network entity.

38. The apparatus of claim 26 , wherein the at least one processor is further configured to:

receive, by the UE from the network entity, a handover command; and

wherein the handover command comprising a handover time indicator associated with a target handover time for the UE to perform a handover operation from a first beam to a second beam.

39. The apparatus of claim 38 , wherein:

the target handover time is determined independent of a measurement report from the UE.

40. The apparatus of claim 39 , wherein:

the measurement report corresponds to the second beam.

41. The apparatus of claim 38 , wherein:

the first beam corresponds to a first platform and the second beam corresponds to the first platform or a second platform.

42. The apparatus of claim 38 , wherein:

the handover operation comprises an intra-satellite handover or an inter-satellite handover.

43. The apparatus of claim 38 , wherein:

the target handover time is determined based on UE capability information, location data, mobility information, a model associated with a flight path of one or more platforms, or a combination thereof.

44. The apparatus of claim 38 , wherein the at least one processor is further configured to:

perform, by the UE, the handover operation with the network entity.

45. The apparatus of claim 26 , wherein the at least one processor is further configured to:

receive, by the UE, a request for a measurement report from the network entity.

46. The apparatus of claim 45 , wherein the at least one processor is further configured to:

transmit, by the UE, the measurement report; and

wherein the measurement report corresponds to a second beam.

47. The apparatus of claim 45 , wherein:

the measurement report is transmitted after performance of a handover operation by the UE to change from a first beam to a second beam.

48. The apparatus of claim 45 , wherein the at least one processor is further configured to:

measure, by the UE, a downlink signal strength of a second beam, a downlink signal quality of the second beam, or a combination thereof; and

wherein the measurement report indicates the downlink signal strength of the second beam, the downlink signal quality of the second beam, or a combination thereof.

49. The apparatus of claim 26 , wherein the at least one processor is further configured to:

receive, by the UE, a radio resource control (RRC) configuration message from the network entity; and

wherein the RRC configuration message includes a handover time indicator, an identifier of the UE, a first indication of a first beam, a second indication of a second beam, an indicator to request a measurement report from the UE, or a combination thereof.

50. An apparatus configured for wireless communication, the apparatus comprising:

at least one processor; and

a memory coupled to the at least one processor,

wherein the at least one processor is configured to:

initiate, by a user equipment (UE), a registration process with a network entity of a non-terrestrial network (NTN) to access the NTN; and

transmit, by the UE to the network entity, UE capability information of the UE, the UE capability information indicating:

an intra-satellite handover delay that corresponds to an antenna repointing delay of the UE.