Method, system, and device for transmitting coding instruction information and for determining pre-coding matrix
View Patent ↗A method, system, and device for transmitting coding instruction information, for use in solving the problem found in the prior art that, as current codebooks are designed for horizontal beamforming/pre-coding, direct application of the codebooks to a three-dimensional beamforming/pre-coding technology causes performance degradation. The method of embodiments of the present invention comprises: a user equipment determines and transmits to a network side first pre-coding instruction information and second pre-coding instruction information, where a first component pre-coding matrix is a block diagonal matrix, a submatrix on the diagonal is equal to the Kronecker product of two matrices, a second component pre-coding matrix is constituted by a weighted column selection vector, with the exception of a P-number of nonzero elements, the remainder of the weighted column selection vector is all zeros, and P is a positive integer. Employment of the method of the embodiments of the present invention increases the performance of the three-dimensional beamforming/pre-coding technology.
1. A method for determining a pre-coding matrix, the method comprising:
receiving, by a network-side device, a first pre-coding indicator and a second pre-coding indicator from a UE; and
determining, by the network-side device, a pre-coding matrix from the first pre-coding indicator and the second pre-coding indicator, and preprocessing data to be transmitted to the UE using the determined pre-coding matrix,
wherein the pre-coding matrix is equal to a matrix as a function of a first component pre-coding matrix and a second component pre-coding matrix, the first component pre-coding matrix is a block diagonal matrix with sub-matrixes on the diagonal being a Kronecker product of two matrixes, and the second component pre-coding matrix is composed of weighted column selection vectors, elements of weighted column selection vector are zeros other than P non-zero elements with P being a positive integer.
2. The method according to claim 1 , wherein determining, by the network-side device, the pre-coding matrix comprises:
determining, by the network-side device, the first component pre-coding matrix corresponding to the first pre-coding indicator and determining the second component pre-coding matrix corresponding to the second pre-coding indicator; and
determining, by the network-side device, that a product of the first component pre-coding matrix and the second component pre-coding matrix is the pre-coding matrix;
or,
wherein determining, by the network-side device, the pre-coding matrix comprises:
determining, by the network-side device, the pre-coding matrix corresponding to the received first pre-coding indicator and second pre-coding indicator according to a preset correspondence relationship between the first pre-coding indicator, the second pre-coding indicator and the pre-coding matrix.
3. The method according to claim 2 , wherein the network-side device determines the first component pre-coding matrix corresponding to the first pre-coding indicator in the equation of:
W
1
=
[
Z
⊗
X
0
0
Z
⊗
X
]
,
or
W
1
=
[
Z
⊗
X
0
0
Z
⊗
XA
]
,
or
W
1
=
[
Z
⊗
X
0
0
ZB
⊗
X
]
,
or
W
1
=
[
Z
⊗
X
0
0
ZB
⊗
XA
]
,
wherein W 1 represents the first component pre-coding matrix; X represents a beam-forming matrix with D H ×M H dimension; Z represents a beam-forming matrix with D V ×M V dimension; A represents a diagonal matrix with M H ×M H dimension; and B represents a diagonal matrix with M V ×M V dimension, wherein M H , D H , D V and M V represent positive integers.
4. The method according to claim 2 , wherein the second component pre-coding matrix is a product of a (2M H M V )×r-dimension matrix and a power normalization coefficient, wherein r represents the number of columns in the pre-coding matrix; and
the network-side device determines the second component pre-coding matrix corresponding to the second pre-coding indicator in the equation of:
W
2
=
[
e
k
1
e
k
2
Λ
e
k
r
α
1
e
k
1
α
2
e
k
2
Λ
α
r
e
k
r
]
M
,
wherein W 2 represents the second component pre-coding matrix; e k i represents a column vector with the length of M H M V and the k i -th element being 1 and all the other elements being 0; and α i represents a complex scalar with a modulus being 1; M H and M V represent positive integers; and M represent the power normalization coefficient.
5. A network-side device, comprising:
a transceiver configured to receive a first pre-coding indicator and a second pre-coding indicator from a UE; and
a processor configured to determine a pre-coding matrix from the first pre-coding indicator and the second pre-coding indicator, and preprocess data to be transmitted to the UE using the determined pre-coding matrix,
wherein the pre-coding matrix is equal to a matrix as a function of a first component pre-coding matrix and a second component pre-coding matrix, the first component pre-coding matrix is a block diagonal matrix with sub-matrixes on the diagonal being a Kronecker product of two matrixes, and the second component pre-coding matrix is composed of weighted column selection vectors, elements of the weighted column selection vector are zeros other than P non-zero elements with P being a positive integer.
6. The network-side device according to claim 5 , wherein the processor is configured:
to determine the first component pre-coding matrix corresponding to the first pre-coding indicator and to determine the second component pre-coding matrix corresponding to the second pre-coding indicator; and to determine that a product of the first component pre-coding matrix and the second component pre-coding matrix is the pre-coding matrix;
or,
wherein the processor is configured:
to determine the pre-coding matrix corresponding to the received first pre-coding indicator and second pre-coding indicator according to a preset correspondence relationship between the first pre-coding indicator, the second pre-coding indicator and the pre-coding matrix.
7. The network-side device according to claim 6 , wherein the processor is configured to determine the first component pre-coding matrix corresponding to the first pre-coding indicator in the equation of:
W
1
=
[
Z
⊗
X
0
0
Z
⊗
X
]
,
or
W
1
=
[
Z
⊗
X
0
0
Z
⊗
XA
]
,
or
W
1
=
[
Z
⊗
X
0
0
ZB
⊗
X
]
,
or
W
1
=
[
Z
⊗
X
0
0
ZB
⊗
XA
]
,
wherein W 1 represents the first component pre-coding matrix; X represents a beam-forming matrix with D H ×M H dimension; Z represents a beam-forming matrix with D V ×M V dimension; A represents a diagonal matrix with M H ×M H dimension; and B represents a diagonal matrix with M V ×M V dimension, wherein M H , D H , D V and M V represent positive integers.
8. The network-side device according to claim 6 , wherein the second component pre-coding matrix is a product of a (2M H M V )×r-dimension matrix and a power normalization coefficient, wherein r represents the number of columns in the pre-coding matrix, and M H and M V represent positive integers, and M represents the power normalization coefficient; and wherein
the second component pre-coding matrix is:
W
2
=
[
e
k
1
e
k
2
Λ
e
k
r
α
1
e
k
1
α
2
e
k
2
Λ
α
r
e
k
r
]
M
,
wherein W 2 represents the second component pre-coding matrix; e k i represents a column vector with the length of M H M V and the k i -th element being 1 and all the other elements being 0; and α i represents a complex scalar with a modulus being 1.