Modeling and Measurements for Multi-path Mitigation with Reconfigurable Intelligent Surfaces

TL;DR

This paper proposes a two-path propagation model for RIS-assisted wireless communications, demonstrating through simulations and experiments that RIS can mitigate multi-path fading and enhance signal quality in high-frequency scenarios.

Contribution

It introduces a novel two-path propagation model considering RIS configurations and compares four RIS types, supported by experimental validation at 35 GHz.

Findings

RIS can effectively mitigate fast fading in wireless channels.

Different RIS configurations vary in their ability to improve received signal power.

Experimental results confirm RIS's potential to enhance wireless communication performance.

Abstract

A reconfigurable intelligent surface (RIS) is capable of manipulating electromagnetic waves with its flexibly configurable unit cells, thus is an appealing technology to resist fast fading caused by multi-path in wireless communications. In this paper, a two-path propagation model for RIS-assisted wireless communications is proposed by considering both the direct path from the transmitter to the receiver and the assisted path provided by the RIS. The proposed propagation model unveils that the phase shifts of RISs can be optimized by appropriate configuration for multi-path fading mitigation. In particular, four types of RISs with different configuration capabilities are introduced and their performances on improving received signal power in virtue of the assisted path to resist fast fading are compared through extensive simulation results. In addition, an RIS operating at 35 GHz is used for experimental measurement. The experimental results verify that an RIS has the ability to combat fast fading and thus improves the receiving performance, which may lay a foundation for further researches.