Beam indication method for multibeam wireless communication system and electronic device using the same

1. A beam indication method for a multibeam wireless communication system, the method comprising:

obtaining a number of candidate beams N and a number of active beams M to determine a plurality of beam groups, wherein the beam groups are selections of the M active beams from the N candidate beams, wherein N>M≥1, each of the beam groups comprises the M active beams, and a number of the beam groups is

N

!

M

!

⁢

(

N

-

M

)

!

;

extracting a plurality of different sets of beam groups from the beam groups respectively comprising the M active beams, wherein the plurality of sets of beam groups comprise a first beam group set;

assigning a first indicator to the first beam group set, wherein the first beam group set comprises at least one of the beam groups respectively comprising the M active beams; and

assigning a beam indicator to one of the beam groups in the first beam group set and generating a beam indication codebook according to the first indicator and the beam indicator, wherein the one of the beam groups in the first beam group set is indicated by both the first indicator of the first beam group set and the beam indicator in the beam indication codebook.

2. The beam indication method according to claim 1 , wherein a number of bits of the first indicator is ┌log 2 K 0,0 ┐, wherein K 0,0 is a number of the plurality of sets of beam groups.

3. The beam indication method according to claim 1 , further comprising:

extracting a plurality of subsets of the beam groups from the first beam group set, wherein the plurality of subsets of the beam groups comprise a first beam group subset; and

assigning a second indicator to the first beam group subset,

wherein the step of assigning the beam indicator to one of the beam groups in the first beam group set to generate the beam indication codebook for beam indication according to the first indicator and the beam indicator comprising:

assigning the beam indicator to one of the beam groups in the first beam group subset of the first beam group set based on a number of the beam groups in the first beam group subset.

4. The beam indication method according to claim 3 , wherein a number of bits of the second indicator is ┌log 2 K 1,0 ┐, wherein K 1,0 is a number of the plurality of subsets of the beam groups.

5. The beam indication method according to claim 3 , wherein a number of bits of the beam indicator is ┌log 2 H α,β ┐, wherein H α,β is the number of the beam groups in the first beam group subset of the first beam group set, α is the first indicator, and β is the second indicator.

6. The beam indication method according to claim 3 , wherein the plurality of sets of beam groups and the plurality of subsets of the beam groups are extracted according to a channel property, and the channel property comprises a multipath scatting condition or mobility condition of a user equipment (UE).

7. The beam indication method according to claim 6 , wherein the plurality of sets of beam groups are extracted from the beam groups based on beam consecutive level of the active beams, as the channel property is the multipath scatting condition; and the plurality of sets of beam groups are extracted based on beam overlap level of the active beams, as the channel property is the mobility condition of the UE.

8. The beam indication method according to claim 3 , further comprising:

transmitting or receiving the first indicator and the second indicator via an L3 signaling or an L2 signaling based on the beam indication codebook.

9. The beam indication method according to claim 8 , wherein the L3 signaling comprises a radio resource control (RRC) message and the L2 signaling comprises a medium access control (MAC) control element (CE).

10. The beam indication method according to claim 1 , further comprising:

transmitting or receiving the beam indicator via an L1 signaling or an L2 signaling based on the beam indication codebook.

11. The beam indication method according to claim 10 , wherein the L1 signaling comprises a downlink control information (DCI) and the L2 signaling comprises a medium access control (MAC) control element (CE).

12. The beam indication method according to claim 1 , wherein the number of candidate beams N is determined in a P1 procedure or a P2 procedure of downlink beam management procedures.

13. The beam indication method according to claim 3 , wherein the first indicator, the second indicator, and the beam indicator are transmitted after a P1 procedure but before a P2 procedure of downlink beam management procedures.

14. The beam indication method according to claim 3 , wherein the first indicator, the second indicator, and the beam indicator are transmitted after a P1 procedure and a P2 procedure of downlink beam management procedures.

15. An electronic device, comprising:

a storage medium; and

a processor coupled to the storage medium, and configured to:

obtain a number of candidate beams N and a number of active beams M to determine a plurality of beam groups, wherein the beam groups are selections of the M active beams from the N candidate beams, wherein N>M≥1, each of the beam groups comprises the M active beams, and a number of the beam groups is

N

!

M

!

⁢

(

N

-

M

)

!

;

extract a plurality of different sets of beam groups from the beam groups respectively comprising the M active beams, wherein the plurality of sets of beam groups comprise a first beam group set;

assign a first indicator to the first beam group set, wherein the first beam group set comprises at least one of the beam groups respectively comprising the M active beams; and

assign a beam indicator to one of the beam groups in the first beam group set and generating a beam indication codebook according to the first indicator and the beam indicator, wherein the one of the beam groups in the first beam group set is indicated by both the first indicator of the first beam group set and the beam indicator in the beam indication codebook.

16. The electronic device according to claim 15 , wherein a number of bits of the first indicator is ┌log 2 K 0,0 ┐, wherein K 0,0 is a number of the plurality of sets of beam groups.

17. The electronic device according to claim 15 , wherein the processor is further configured to:

extract a plurality of subsets of the beam groups from the first beam group set, wherein the plurality of subsets of the beam groups comprise a first beam group subset; and

assign a second indicator to the first beam group subset,

wherein the processor is further configured to:

assign the beam indicator to one of the beam groups in the first beam group subset of the first beam group set based on a number of the beam groups in the first beam group subset.

18. The electronic device according to claim 17 , wherein a number of bits of the second indicator is ┌log 2 K 1,0 ┐, wherein K 1,0 is a number of the plurality of subsets of the beam groups.

19. The electronic device according to claim 17 , wherein a number of bits of the beam indicator is ┌log 2 H α,β ┐, wherein H α,β is the number of the beam groups in the first beam group subset of the first beam group set, a is the first indicator, and β is the second indicator.

20. The electronic device according to claim 17 , wherein the plurality of sets of beam groups and the plurality of subsets of the beam groups are extracted according to a channel property, and the channel property comprises a multipath scatting condition or a mobility condition of a user equipment (UE).

21. The electronic device according to claim 20 , wherein the plurality of sets of beam groups are extracted from the beam groups based on beam consecutive level of the active beams, as the channel property is the multipath scatting condition; and the plurality of sets of beam groups are extracted based on beam overlap level of the active beams, as the channel property is the mobility condition of the UE.

22. The electronic device according to claim 17 , wherein the electronic device further comprises a transceiver coupled to the processor, and the processor further configured to:

transmit or receive the first indicator and the second indicator via an L3 signaling or an L2 signaling based on the beam indication codebook.

23. The electronic device according to claim 22 , wherein the L3 signaling comprises a radio resource control (RRC) message and the L2 signaling comprises a medium access control (MAC) control element (CE).

24. The electronic device according to claim 15 , wherein the electronic device further comprises a transceiver coupled to the processor, and the processor further configured to:

transmit or receive the beam indicator via an L1 signaling or an L2 signaling based on the beam indication codebook.

25. The electronic device according to claim 24 , wherein the L1 signaling comprises a downlink control information (DCI) and the L2 signaling comprises a medium access control (MAC) control element (CE).

26. The electronic device according to claim 15 , wherein a number of candidate beams N is determined in a P1 procedure or a P2 procedure of downlink beam management procedures.

27. The electronic device according to claim 17 , wherein the first indicator, the second indicator, and the beam indicator are transmitted after a P1 procedure but before a P2 procedure of downlink beam management procedures.

28. The electronic device according to claim 17 , wherein the first indicator, the second indicator, and the beam indicator are transmitted after a P1 procedure and a P2 procedure of downlink beam management procedures.