Channel state information reporting method and apparatus

1. A channel state information reporting method, comprising:

obtaining, by a terminal device, first indication information, wherein the first indication information indicates a differential value between channel state information of a first antenna port set and channel state information of a second antenna port set, the first antenna port set comprises x antenna ports of the terminal device, the second antenna port set comprises m antenna ports of the terminal device, the first antenna port set is different from the second antenna port set, x and m are positive integers, and the channel state information of the first antenna port set comprises first amplitude information and/or the channel state information of the second antenna port set comprises second amplitude information; and

sending, by the terminal device, the first indication information.

2. The method according to claim 1 , wherein the first indication information is a wideband parameter, or the first indication information is a subband parameter.

3. The method according to claim 1 , wherein the channel state information of the first antenna port set that comprises the first amplitude information is associated with a channel matrix (G u ) of the first antenna port set; and/or

the channel state information of the second antenna port set that comprises the second amplitude information is associated with a channel matrix (G d ) of the second antenna port set, wherein

G d is a matrix with m rows and M columns, G u is a matrix with x rows and M columns, and M is a positive integer.

4. The method according to claim 3 , wherein the first amplitude information is determined based on any one of the following elements:

an element whose amplitude information has a largest value in at least one row of elements of G u , an element whose amplitude information has a largest value in at least one column of elements of a matrix (W 2,u ) corresponding to G u , a singular value whose amplitude information has a largest value in at least one singular value of G u , or an eigenvalue whose amplitude information has a largest value in at least one eigenvalue of G u ; and/or

the second amplitude information is determined based on any one of the following elements:

an element whose amplitude information has a largest value in at least one row of elements of G d , an element whose amplitude information has a largest value in at least one column of elements of a matrix (W 2,d ) corresponding to G d , an eigenvalue whose amplitude information has a largest value in at least one eigenvalue of G d , or a singular value whose amplitude information has a largest value in at least one singular value of G d , wherein

G u T (l u )=W 1 ×W 2,u (l u ), G d T (l d )=W 1 ×W 2,d (l d ), X T represents transposition of a matrix (X), X(l u ) represents an l u th column of the matrix X, X(l d ) represents an l d th column of X, W 1 is an M*N matrix, W 2,u is an N*x matrix, W 2,d is an N*m matrix, N is a positive integer, l u ∈{1, 2, . . . , x}, and l d ∈{1, 2, . . . , m}.

5. The method according to claim 3 , wherein the first amplitude information is determined based on an element whose amplitude information has a largest value in at least one row of elements of G u ; and

the second amplitude information comprises n sub-elements, an ith sub-element in the n sub-elements is determined based on an element whose amplitude information has a largest value in M elements in an ith row in n rows of G d n is a positive integer, and i∈{1, 2, . . . , n}.

6. The method according to claim 3 , wherein the first amplitude information is determined based on an element whose amplitude information has a largest value in at least one column of elements of a matrix (W 2,u ) corresponding to G u ; and

the second amplitude information comprises n sub-elements, an ith sub-element in the n sub-elements is determined based on an element whose amplitude information has a largest value in N elements in an ith column in n columns of a matrix (W 2,d ) corresponding to G d n is a positive integer, and i∈{1, 2, . . . n}, wherein

G u T (l u )=W 1 ×W 2,u (l u ), G d T (l d )=W 1 ×W 2,d (l d ), X T represents transposition of a matrix X, X(l u ) represents an l u column of the matrix X, X(l d ) represents an l d column of X, W 1 is an M*N matrix, W 2,u is an N*x matrix, W 2,d is an N*m matrix, N is a positive integer, l u ∈{1, 2, . . . , x}, and l d ∈{1, 2, . . . , m}.

7. The method according to claim 3 , wherein the first amplitude information is determined based on an average value of amplitude information of at least two elements of G u , and the second amplitude information is determined based on an average value of amplitude information of at least two elements of G d ; or

the first amplitude information is determined based on an average value of amplitude information of at least two elements of a matrix (W 2,u ) corresponding to G u , and the second amplitude information is determined based on an average value of amplitude information of at least two elements of a matrix (W 2,d ) corresponding to G d , wherein

G u T (l u )=W 1 ×W 2,u (l u ), G d T (l d )=W 1 ×W 2,d (l d ), X T represents transposition of a matrix X, X(l u ) represents an l u column of the matrix X, X(l d ) represents an l d column of X, W 1 is an M*N matrix, W 2,u is an N*x matrix, W 2,d is an N*m matrix, N is a positive integer, l u ∈{1, 2, . . . , x}, and l d ∈{1, 2, . . . , m}.

8. A channel state information reporting method, comprising:

sending, by a network device, a first reference signal; and

receiving, by the network device, first indication information obtained by a terminal device based on the first reference signal, wherein the first indication information indicates a differential value between channel state information of a first antenna port set and channel state information of a second antenna port set, the first antenna port set comprises x antenna ports of the terminal device, the second antenna port set comprises m antenna ports of the terminal device, the first antenna port set is different from the second antenna port set, x and m are positive integers, and the channel state information of the first antenna port set comprises first amplitude information and/or the channel state information of the second antenna port set comprises second amplitude information.

9. The method according to claim 8 , wherein the first indication information is a wideband parameter, or the first indication information is a subband parameter.

10. The method according to claim 8 , wherein the channel state information of the first antenna port set the comprises the first amplitude information is associated with a channel matrix (G u ) of the first antenna port set; and/or

the channel state information of the second antenna port set that comprises the second amplitude information is associated with a channel matrix (G d ) of the second antenna port set, wherein

G d is a matrix with m rows and M columns, G u is a matrix with x rows and M columns, and M is a positive integer.

11. The method according to claim 10 , wherein the first amplitude information is determined based on any one of the following elements:

an element whose amplitude information has a largest value in at least one row of elements of G u , an element whose amplitude information has a largest value in at least one column of elements of a matrix (W 2,u ) corresponding to G u , a singular value whose amplitude information has a largest value in at least one singular value of G u , or an eigenvalue whose amplitude information has a largest value in at least one eigenvalue of G u ; and/or

the second amplitude information is determined based on any one of the following elements:

an element whose amplitude information has a largest value in at least one row of elements of G d , an element whose amplitude information has a largest value in at least one column of elements of a matrix (W 2,d ) corresponding to G d , an eigenvalue whose amplitude information has a largest value in at least one eigenvalue of G d , or a singular value whose amplitude information has a largest value in at least one singular value of G d , wherein

G u T (l u )=W 1 ×W 2,u (l u ), G d T (l d )=W 1 ×W 2,d (l d ), X T represents transposition of a matrix X, X(l u ) represents an l u column of the matrix X, X(l d ) represents an l d column of X, W 1 is an M*N matrix, W 2,u is an N*x matrix, W 2,d is an N*m matrix, N is a positive integer, l u ∈{1, 2, . . . , x}, and l d ∈{1, 2, . . . , m}.

12. The method according to claim 10 , wherein the first amplitude information is determined based on an element whose amplitude information has a largest value in at least one row of elements of G u ; and

the second amplitude information comprises n sub-elements, an ith sub-element in the n sub-elements is determined based on an element whose amplitude information has a largest value in M elements in an ith row in n rows of G d n is a positive integer, and i∈{1,2, . . . , n}.

13. The method according to claim 10 , wherein the first amplitude information is determined based on an element whose amplitude information has a largest value in at least one column of elements of a matrix (W 2,u ) corresponding to G u ; and

the second amplitude information comprises n sub-elements, an ith sub-element in the n sub-elements is determined based on an element whose amplitude information has a largest value in N elements in an ith column in n columns of a matrix (W 2,d ) corresponding to G d , n is a positive integer, and i∈{1, 2, . . . ,}, wherein

G u T (l u )=W 1 ×W 2,u (l u ), G d T (l d )=W 1 ×W 2,d (l d ), X T represents transposition of a matrix X, X(l u ) represents an l u column of the matrix X, X(l d ) represents an l d column of X, W 1 is an M*N matrix, W 2,u is an N*x matrix, W 2,d is an N*m matrix, N is a positive integer, l u ∈{1, 2, . . . , x}, and l d ∈{1, 2, . . . , m}.

14. An apparatus, comprising:

at least one processor; and

at least one memory, coupled with the processor, wherein the at least one memory stores a computer program which, when executed by the at least one processor, causes the apparatus to:

obtain first indication information, wherein the first indication information indicates a differential value between channel state information of a first antenna port set and channel state information of a second antenna port set, the first antenna port set comprises x antenna ports of a terminal device, the second antenna port set comprises m antenna ports of the apparatus, the first antenna port set is different from the second antenna port set, x and m are positive integers, and the channel state information of the first antenna port set comprises first amplitude information and/or the channel state information of the second antenna port set comprises second amplitude information, and send the first indication information.

15. The apparatus according to claim 14 , wherein the first indication information is a wideband parameter, or the first indication information is a subband parameter.

16. The apparatus according to claim 14 , wherein the channel state information of the first antenna port set that comprises the first amplitude information is associated with a channel matrix (G u ) of the first antenna port set; and/or

the channel state information of the second antenna port set that comprises the second amplitude information is associated with a channel matrix (G d ) of the second antenna port set, wherein

G d is a matrix with m rows and M columns, G u is a matrix with x rows and M columns, and M is a positive integer.

17. The apparatus according to claim 16 , wherein the first amplitude information is determined based on any one of the following elements:

an element whose amplitude information has a largest value in at least one row of elements of G u , an element whose amplitude information has a largest value in at least one column of elements of a matrix (W 2,u ) corresponding to G u , a singular value whose amplitude information has a largest value in at least one singular value of G u , or an eigenvalue whose amplitude information has a largest value in at least one eigenvalue of G u ; and/or

the second amplitude information is determined based on any one of the following elements:

an element whose amplitude information has a largest value in at least one row of elements of G d , an element whose amplitude information has a largest value in at least one column of elements of a matrix (W 2,d ) corresponding to G d , an eigenvalue whose amplitude information has a largest value in at least one eigenvalue of G d , or a singular value whose amplitude information has a largest value in at least one singular value of G d , wherein

G u T (l u )=W 1 ×W 2,u (l u ), G d T (l d )=W 1 ×W 2,d (l d ), X T represents transposition of a matrix X, X(l u ) represents an l u column of the matrix X, X(l d ) represents an l d column of X, W 1 is an M*N matrix, W 2,u is an N*x matrix, W 2,d is an N*m matrix, N is a positive integer, l u ∈{1, 2, . . . , x}, and l d ∈{1, 2, . . . , m}.

18. The apparatus according to claim 16 , wherein the first amplitude information is determined based on an element whose amplitude information has a largest value in at least one row of elements of G u ; and

the second amplitude information comprises n sub-elements, an ith sub-element in the n sub-elements is determined based on an element whose amplitude information has a largest value in M elements in an ith row in n rows of G d n is a positive integer, and i∈{1, 2, . . . , n}.

19. The apparatus according to claim 16 , wherein the first amplitude information is determined based on an element whose amplitude information has a largest value in at least one column of elements of a matrix (W 2,u ) corresponding to G u ; and

the second amplitude information comprises n sub-elements, an ith sub-element in the n sub-elements is determined based on an element whose amplitude information has a largest value in N elements in an ith column in n columns of a matrix (W 2,d ) corresponding to G d n is a positive integer, and i∈{1, 2, . . . , n}, wherein

G u T (l u )=W 1 ×W 2,u (l u ), G d T (l d )=W 1 ×W 2,d (l d ), X T represents transposition of a matrix X, X(l u ) represents an l u column of the matrix X, X(l d ) represents an l d column of X, W 1 is an M*N matrix, W 2,u is an N*x matrix, W 2,d is an N*m matrix, N is a positive integer, l u ∈{1, 2, . . . , x}, and l d ∈{1, 2, . . . , m}.

20. The apparatus according to claim 14 , wherein the apparatus is the terminal device.