A self-adaptive design method of phase-shift matrix of intelligent reflective surface in large-scale mimo system

Abstract

The invention provides a self-adaptive design method for the phase shift matrix of an intelligent reflection surface in a massive MIMO system. In the downlink, the base station transmits signals through a large-scale antenna array, and the intelligent reflector performs a phase-shift operation on the received signal, and then reflects it to the user. According to the corresponding communication environment, the present invention adaptively selects an optimized phase shift matrix design method or a random phase shift matrix design method. Optimal Phase Shift Matrix Design By transmitting a single-frequency signal, the phase shift matrix of the smart reflector is optimized under the criterion of maximizing the received power of the user end. A random phase shift matrix design randomly determines the phase of each reflective element. The invention is simple in operation and low in computational complexity, and both phase shift matrix design methods can obtain higher power efficiency and spectrum efficiency, and does not require any channel state information of the intelligent reflector, and is suitable for large-scale MIMO communication using the intelligent reflector The design and implementation of the system is of great significance.

Description

technical field [0001] The invention belongs to the technical field of wireless communication, and in particular relates to an adaptive design method of an intelligent reflection surface phase-shift matrix in a large-scale MIMO system. Background technique [0002] As a key technology for the fifth generation (5G) and future mobile communications, massive MIMO (Multiple Input Multiple Output) technology can achieve wide cell coverage through large-scale antenna arrays while utilizing spatial degrees of freedom to obtain high spectral efficiency. These advantages of the massive MIMO system can meet the rapidly increasing data transmission demand in the future 5G era. However, in practical communication systems, some occlusions or obstacles, such as buildings, trees, cars, and even animals, will inevitably appear. To solve this problem and ensure a smooth user experience, a typical solution is to add an additional transmission link to maintain the communication link. For exa...

AI Technical Summary

Problems solved by technology

Unlike analog phase shifters, digital phase shifters can only make limited phase adjustments

In addition, since the smart reflector only passively receives and forwards the signal, its channel vector is difficult to estimate

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