Transmit channel initial phase correction method and apparatus

Patent metadata

Field	Value
Publication number	US-12057904-B2
Application number	US-202318154997-A
Country	US
Kind code	B2
Filing date	Jan 16, 2023
Priority date	Jul 17, 2020
Publication date	Aug 6, 2024
Grant date	Aug 6, 2024

Abstract

An apparatus: obtains K downlink channel weight matrices based on K pieces of downlink channel information sent by K UEs, where the downlink channel information is fed back by the UE in response to a preset reference signal sent by the base station, the downlink channel weight matrix is an NT×rank-dimensional matrix, and rank is a quantity of signal streams received by the UE; obtains K×rank first initial phase difference matrices and K×rank second initial phase difference matrices based on the K downlink channel weight matrices and a first polarization direction and a second polarization direction of transmit channels of the base station; obtains a cell initial phase difference matrix based on the K×rank first initial phase difference matrices and the K×rank second initial phase difference matrices; and implements initial phase correction of the transmit channels based on the cell initial phase difference matrix.

First claim

What is claimed is:

1. A method, comprising:
obtaining, by a base station, K downlink channel weight matrices based on K pieces of downlink channel information sent by K user equipment (UEs), wherein K is a positive integer, the K pieces of downlink channel information are fed back by the K UEs in response to a preset reference signal sent by the base station, each downlink channel weight matrix is an N T ×rank-dimensional matrix, N T is a quantity of transmit channels of the base station, and rank is a quantity of signal streams received by a UE corresponding to the respective downlink channel weight matrix;
obtaining K×rank first initial phase difference matrices based on the K downlink channel weight matrices and a first polarization direction of the transmit channels of the base station, and obtaining K×rank second initial phase difference matrices based on the K downlink channel weight matrices and a second polarization direction of the transmit channels of the base station, wherein the first polarization direction is different from the second polarization direction, the K×rank first initial phase difference matrices and the K×rank second initial phase difference matrices are all M×N-dimensional matrices, N T =2×M×N, and both M and N are positive integers;
obtaining a cell initial phase difference matrix based on the K×rank first initial phase difference matrices and the K×rank second initial phase difference matrices; and
implementing initial phase correction of the transmit channels of the base station based on the cell initial phase difference matrix.

2. The method according to claim 1 , wherein each piece of downlink channel information comprises at least one precoding matrix indicator (PMI) fed back by a UE that sends the respective piece of downlink channel information or a sounding reference signal (SRS) fed back by the UE that sends the respective piece of downlink channel information.

3. The method according to claim 1 , wherein the K pieces of downlink channel information are sounding reference signals (SRSs) fed back by the K UEs, and obtaining, by the base station, the K downlink channel weight matrices based on the K pieces of downlink channel information sent by the K UEs comprises:
obtaining K downlink channel matrices based on the K pieces of downlink channel information, wherein each downlink channel matrix is an N R ×N T -dimensional matrix, and N R is a quantity of receive channels of the UE that sends a piece of downlink channel information corresponding to the respective downlink channel matrix; and
performing singular value decomposition on the K downlink channel matrices to obtain K×rank right singular vectors, wherein at least one downlink channel weight matrix comprises rank right singular vectors, and at least one right singular vector comprises N T elements.

4. The method according to claim 1 , wherein obtaining the K×rank first initial phase difference matrices based on the K downlink channel weight matrices and the first polarization direction of the transmit channels of the base station, and obtaining the K×rank second initial phase difference matrices based on the K downlink channel weight matrices and the second polarization direction of the transmit channels of the base station comprises:
obtaining K×rank first phase matrices based on the K downlink channel weight matrices and the first polarization direction, and obtaining K×rank second phase matrices based on the K downlink channel weight matrices and the second polarization direction, wherein the K×rank first phase matrices and the K×rank second phase matrices are all M×N-dimensional matrices; and
obtaining the K×rank first initial phase difference matrices based on the K×rank first phase matrices, and obtaining the K×rank second initial phase difference matrices based on the K×rank second phase matrices.

5. The method according to claim 1 , wherein the transmit channels of the base station comprise transmit channels of M rows and N columns whose polarization directions are the first polarization direction, and transmit channels of M rows and N columns whose polarization directions are the second polarization direction;
wherein any element in a first phase matrix corresponding to at least one downlink channel weight matrix is a phase of a corresponding transmit channel whose polarization direction is the first polarization direction, and any element in a second phase matrix corresponding to at least one downlink channel weight matrix is a phase of a corresponding transmit channel whose polarization direction is the second polarization direction; and
wherein any element in each first initial phase difference matrix is a phase compensation value of a corresponding transmit channel whose polarization direction is the first polarization direction, and any element in each second initial phase difference matrix is a phase compensation value of a corresponding transmit channel whose polarization direction is the second polarization direction.

6. The method according to claim 5 , wherein each first phase matrix φ + and each second phase matrix φ − are as follows:

φ
+

=

[

φ

M
,
1

φ

M
,
2

…

…

…

φ

M
,
N

⋮

⋮

⋱

⋮

⋱

⋮

φ

m
,
1

φ

m
,
2

…

Assignees

• Huawei Tech Co Ltd

Inventors

• Jiang Xu
• Yang Ye
• Zhang Jiapeng
• Chen Kai

Classifications

• H04B7/0682

  using phase diversity (e.g. phase sweeping) · CPC title

• H04B7/0469

  taking special antenna structures, e.g. cross polarized antennas into account · CPC title

• H04B7/10

  Polarisation diversity; Directional diversity · CPC title

• H04B7/0456 Primary

  Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting · CPC title

• H04B17/12 Primary

  of transmit antennas, e.g. of the amplitude or phase · CPC title