Millimeter wave communication system hybrid precoding method based on zero forcing

Abstract

The invention discloses a millimeter wave communication system hybrid precoding method based on zero forcing. The method comprises the steps of establishing a zero forcing precoding matrix according to a channel matrix; decomposing the zero forcing precoding matrix into a product of a unitary matrix and an upper triangular matrix through QR decomposition; matching the unitary matrix in the step 2 through utilization of an array manifold vector and establishing an analog end precoding matrix, wherein elements in the matrix have constant modulus characteristics; obtaining a digital end precoding matrix through utilization of the analog end precoding matrix and the zero forcing precoding matrix, wherein a final hybrid precoding matrix represents the product of the analog end precoding matrix and the zero forcing precoding matrix. In a millimeter wave downlink system of which the number of transmitting antennas is greater than that of receiving antennas, the number of radio frequency links required by the method is the same to that of the receiving antennas. Compared with the traditional ZF precoding of which number of radio frequency links is the same to that of the transmitting antennas, the method has the advantage that the number of the radio frequency links is fewer, so the hardware cost and extra hardware device power cost of the system are reduced.

Description

technical field [0001] The invention relates to a hybrid precoding method for a millimeter wave communication system based on zero forcing, and belongs to the technical field of wireless communication precoding. Background technique [0002] Multiple-Input Multiple-Output (MIMO) technology refers to the use of multiple transmitting antennas and receiving antennas at the transmitting end and receiving end respectively, and signals are transmitted and received through multiple antennas at the transmitting end and receiving end, thereby improving communication quality. It can make full use of space resources and bring additional diversity and multiplexing gains to the system. Whether it is a single-user MIMO or multi-user MIMO system, a basic problem is to eliminate the interference between data streams or between user signals. [0003] In order to solve the above basic problems, the current processing method mainly uses the channel information CSI to precode the transmitted ...

AI Technical Summary

Problems solved by technology

Due to the need to use a large number of hardware devices such as D / A converters, mixers and power amplifiers (that is, the so-called radio frequency link), the traditional method makes the millimeter wave system have problems of excessive hardware cost and power consumption.

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