Mode switching method for reducing training overhead in intelligent reflective surface-assisted communication system

Abstract

The invention discloses a mode switching method for reducing training overhead in an intelligent reflective surface assisted communication system. The system includes a single-antenna base station, a single-antenna user terminal and an intelligent reflective surface composed of N reflective elements, wherein the single-antenna user terminal is directed to The single-antenna base station transmits data, but the user-base station direct link is blocked by obstacles, and the data can only be sent to the single-antenna base station through the smart reflector; the controller determines the appropriate reflection scheme for the smart reflector and dynamically adjusts its phase To increase the achievable data rate of the system; and the necessary information for phase shift adjustment can be obtained through uplink training at the base station and transmitted to the controller of the smart reflector through the control link. The method comprehensively utilizes statistics and instantaneous channel state information, and properly selects an intelligent reflection surface reflection scheme, which can effectively reduce training overhead and improve system performance.

Description

technical field [0001] The invention relates to the field of communication technology, in particular to a mode switching method for reducing training overhead in an intelligent reflective surface assisted communication system. Background technique [0002] With the commercialization of the fifth-generation (The 5-th Generation, 5G) mobile communication system, the research on the sixth-generation (The 6-th Generation, 6G) mobile communication technology has started, pursuing faster and more reliable data transmission Connect with everything. Reconfigurable Intelligent Surfaces (RIS) can significantly improve the spectral efficiency and energy efficiency of wireless networks by reconfiguring the wireless propagation environment. Specifically, the smart reflector is composed of a series of passive components, and each component can independently cause some changes of the incident signal such as phase, amplitude, frequency and so on. When the quality of direct communication i...

AI Technical Summary

Problems solved by technology

However, due to the passive reflection of smart reflector elements, in terms of training duration, the channel training overhead usually grows linearly with the number of smart reflector elements

Although a larger N increases the signal strength, it also leads to a longer training duration, which reduces the effective data transmission time in the limited coherence time

In order to reduce the training overhead of smart reflector-assisted communication, one solution is to activate only part of the smart reflector elements for transmission, however, this is at the cost of the smart reflector elements not being fully utilized

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