Precoding matrix determining method, and base station

Abstract

The invention discloses a precoding matrix determining method, and a base station, in order to increase the antenna gains of antennas of the base station and improving the signal strength, when the number of pilot frequency ports is smaller than the number of the antennas of the base station. The method disclosed by the invention comprises the following steps: the base station obtains channel state information fed back by a terminal according to a mapping matrix, wherein the mapping matrix is a matrix obtained by mapping the pilot frequency ports of the base station onto the antennas of the base station in a one-to-one correspondence manner, the total number of the pilot frequency ports is N, the total number of the antennas of the base station is M, the M is greater than the N, and the Mand the N are positive integers not less than 2; the base station determines a first precoding matrix according to the channel state information, wherein the first precoding matrix comprises sending weights of N antennas; the base station determines a second precoding matrix according to the first precoding matrix, wherein the second precoding matrix comprises sending weights of M antennas, and the second precoding matrix is used for sending data on the antennas of the base station.

Description

technical field [0001] The present application relates to the field of communication technologies, and in particular to a method for determining a precoding matrix and a base station. Background technique [0002] In a long term evolution (LTE) system, before the base station transmits downlink data to the terminal through the base station antenna, the base station must first estimate the channel between the base station antenna and the terminal to obtain channel state information (CSI). , the specific method is that the base station sends a pilot signal to the terminal, the terminal performs channel estimation according to the received pilot signal to obtain the channel, and the terminal feeds back the CSI information corresponding to the channel to the base station. The base station selects an appropriate precoding matrix according to the above channel state information, and uses the precoding matrix to send downlink data to the terminal on the base station antenna. [00...

AI Technical Summary

Problems solved by technology

In the case where the total number of pilot ports is less than the total number of antennas, the base station antennas are not fully utilized. Since the actual number of antennas used is less than the total number of antennas, the gain of the precoding matrix finally obtained by the base station is reduced, resulting in the loss of the gain of the antenna matrix array.

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