Communication method, apparatus, chip, storage medium, and program product
In accordance with an embodiment, a communication method includes: sending, by a first device, a first reference signal of M (M>2) ports; and receiving, by the first device, first indication information that indicates a first precoding matrix in a target codebook. The first precoding matrix is associated with the first reference signal, and the target codebook includes at least one target precoding matrix that is a partially coherent precoding matrix or a coherent precoding matrix.
1. A communication method, wherein the method comprises:
sending, by a first device, a first reference signal of M ports, wherein M is an integer greater than 2; and
receiving, by the first device, first indication information, wherein the first indication information indicates a first precoding matrix in a target codebook, the first precoding matrix is associated with the first reference signal, the target codebook comprises at least one target precoding matrix, and a quantity of rows in the target precoding matrix is M, wherein non-zero elements of the target precoding matrix include elements in
{
e
j
n
π
N
A
}
,
wherein n comprises integers 0 to N−1, N is a number of rows having the non-zero elements, j is an imaginary unit, A is a positive constant, and
the target precoding matrix has only two rows that comprise non-zero elements, the target precoding matrix has two columns, N=2, and the target precoding matrix is a partially coherent precoding matrix, or
the target precoding matrix has only three rows that comprise non-zero elements, N=3, and the target precoding matrix is a partially coherent precoding matrix or a coherent precoding matrix, or
the target precoding matrix has only K rows that comprise non-zero elements, N=K, K is an integer less than M and not less than 4, and the target precoding matrix is a partially coherent precoding matrix.
2. The method according to claim 1 , wherein:
the partially coherent precoding matrix is a precoding matrix in which one column comprises more than one and less than M non-zero elements; and
the coherent precoding matrix is a precoding matrix in which all columns comprise M non-zero elements.
3. The method of claim 1 , wherein:
the first indication information comprises indication information of a first transmit precoding matrix indicator (TPMI); and
the first TPMI is an index of the first precoding matrix in the target codebook.
4. The method of claim 1 , wherein:
when only two rows in the target precoding matrix comprise non-zero elements, the two rows in the target precoding matrix that comprise the non-zero elements are set to
[
a
b
c
d
]
,
a, b, c, and d are elements in {1/A 1 ,−1/A 1 , j/A 1 ,−j/A 1 };
j is an imaginary unit; and
A 1 =A is the positive constant.
5. The method of claim 4 , wherein the two rows in the target precoding matrix that comprise non-zero elements each may have any row location in the target precoding matrix, and a matrix formed by the two rows in the target precoding matrix that comprise non-zero elements is
[
a
b
c
d
]
.
6. The method of claim 1 , wherein when only three rows in the target precoding matrix comprise non-zero elements, the non-zero elements are elements in
{
1
A
2
,
e
j
π
3
A
2
,
e
j
2
π
3
A
2
,
-
1
A
2
,
-
e
j
2
π
3
A
2
,
-
e
j
π
3
A
2
}
,
wherein j is an imaginary unit, A 2 =A is the positive constant, and the three rows in the target precoding matrix that comprise the non-zero elements each may have any row location.
7. The method of claim 1 , wherein when only K rows in the target precoding matrix comprise non-zero elements, the non-zero elements are elements in
{
e
jk
π
K
A
3
}
,
wherein k=0, 1, 2, . . . , K−1, j is an imaginary unit, A 3 =A is the positive constant, and the K rows in the target precoding matrix that comprise the non-zero elements each may have any row location.
8. The method of claim 1 , wherein, when a quantity of columns in the target precoding matrix is greater than 1, any two columns in the target precoding matrix are orthogonal column vectors.
9. The method of claim 1 , wherein a waveform to which the target precoding matrix is applicable comprises a discrete Fourier transformation spread orthogonal frequency division multiplexing DFT-s-OFDM waveform or a cyclic prefix orthogonal frequency division multiplexing CP-OFDM waveform.
10. A communication method, comprising:
receiving, by a second device, a first reference signal of M ports, wherein M is an integer greater than 2; and
sending, by the second device, first indication information, wherein the first indication information indicates a first precoding matrix in a target codebook, the first precoding matrix is associated with the first reference signal, the target codebook comprises at least one target precoding matrix, and a quantity of rows in the target precoding matrix is M, wherein non-zero elements of the target precoding matrix include elements in
{
e
j
n
π
N
A
}
,
wherein n comprises integers 0 to N−1, N is a number of rows having the non-zero elements, j is an imaginary unit, A is a positive constant, and
the target precoding matrix has only two rows that comprise non-zero elements, N=2, the target precoding matrix has two columns, and the target precoding matrix is a partially coherent precoding matrix; or
the target precoding matrix has only three rows that comprise non-zero elements, N=3, and the target precoding matrix is a partially coherent precoding matrix or a coherent precoding matrix; or
the target precoding matrix has only K rows that comprise non-zero elements, N=K, K is an integer less than M and not less than 4, and the target precoding matrix is a partially coherent precoding matrix.
11. The method of claim 10 , wherein:
the partially coherent precoding matrix is a precoding matrix in which one column comprises more than one and less than M non-zero elements; and
the coherent precoding matrix is a precoding matrix in which all columns comprise M non-zero elements.
12. The method of claim 10 , wherein the first indication information comprises indication information of a first transmit precoding matrix indicator (TPMI), and the first TPMI is an index of the first precoding matrix in the target codebook.
13. A non-transitory computer-readable storage medium with a computer program code stored thereon, wherein the computer program code comprises instructions that, when run on a first device, the first device is enabled to perform:
sending a first reference signal of M ports, wherein M is an integer greater than 2; and
receiving first indication information, wherein the first indication information indicates a first precoding matrix in a target codebook, the first precoding matrix is associated with the first reference signal, the target codebook comprises at least one target precoding matrix, and a quantity of rows in the target precoding matrix is M, wherein non-zero elements of the target precoding matrix include elements in
{
e
j
n
π
N
A
}
,
wherein n comprises integers 0 to N−1, N is a number of rows having the non-zero elements, j is an imaginary unit, A is a positive constant, and
the target precoding matrix has only two rows that comprise non-zero elements, N=2, the target precoding matrix has two columns, and the target precoding matrix is a partially coherent precoding matrix, or
the target precoding matrix has only three rows that comprise non-zero elements, N=3, and the target precoding matrix is a partially coherent precoding matrix or a coherent precoding matrix, or
the target precoding matrix has only K rows that comprise non-zero elements, N=K, K is an integer less than M and not less than 4, and the target precoding matrix is a partially coherent precoding matrix.
14. The non-transitory computer-readable storage medium of claim 13 , wherein:
the partially coherent precoding matrix is a precoding matrix in which one column comprises more than one and less than M non-zero elements; and
the coherent precoding matrix is a precoding matrix in which all columns comprise M non-zero elements.
15. The non-transitory computer-readable storage medium of claim 13 , wherein the first indication information comprises indication information of a first transmit precoding matrix indicator (TPMI), and the first TPMI is an index of the first precoding matrix in the target codebook.
16. The non-transitory computer-readable storage medium of claim 13 , wherein:
when only two rows in the target precoding matrix comprise non-zero elements, the two rows in the target precoding matrix that comprise the non-zero elements are set to
[
a
b
c
d
]
;
a, b, c, and d are elements in {1/A 1 ,−1/A 1 , j/A 1 ,−j/A 1 };
j is an imaginary unit; and
A 1 =A is the positive constant.
17. The non-transitory computer-readable storage medium of claim 16 , wherein the two rows in the target precoding matrix that comprise non-zero elements each may have any row location in the target precoding matrix, and a matrix formed by the two rows in the target precoding matrix that comprise non-zero elements is
[
a
b
c
d
]
.
18. The non-transitory computer-readable storage medium of claim 13 , wherein when only three rows in the target precoding matrix comprise non-zero elements, the non-zero elements are elements in
{
1
A
2
,
e
j
π
3
A
2
,
e
j
2
π
3
A
2
,
-
1
A
2
,
-
e
j
2
π
3
A
2
,
-
e
j
π
3
A
2
}
,
wherein j is an imaginary unit, A 2 =A is the positive constant, and the three rows in the target precoding matrix that comprise the non-zero elements each may have any row location.
19. The non-transitory computer-readable storage medium of claim 13 , wherein when only K rows in the target precoding matrix comprise non-zero elements, the non-zero elements are elements in
{
e
jk
π
K
A
3
}
,
wherein k=0, 1, 2, . . . , K−1, j is an imaginary unit, A 3 =A is the positive constant, and the K rows in the target precoding matrix that comprise the non-zero elements each may have any row location.
20. The non-transitory computer-readable storage medium of claim 13 , wherein when a quantity of columns in the target precoding matrix is greater than 1, any two columns in the target precoding matrix are orthogonal column vectors.