RIS Assisted Wireless Communication: Advanced Modeling, Simulation, and Analytical Insights

TL;DR

This paper introduces a comprehensive simulation framework for RIS-assisted communication, analyzing system performance, and proposing an optimal alignment algorithm to reduce bit errors, thereby advancing understanding of RIS system design.

Contribution

It develops a detailed simulation model that integrates RIS antenna design with communication processes and proposes an optimal alignment method to improve system performance.

Findings

Larger array sizes increase BER due to aperture fill time effects.

Higher baseband symbol frequencies exacerbate aperture fill time issues.

The proposed matching-based alignment significantly reduces BER compared to pilot-based methods.

Abstract

This article presents a novel perspective to model and simulate reconfigurable intelligent surface (RIS)-assisted communication systems. Traditional methods in antenna design often rely on array method to simulate, whereas communication system modeling tends to idealize antenna behavior. Neither approach sufficiently captures the detailed characteristics of RIS-assisted communication. To address this limitation, we propose a comprehensive simulation framework that jointly models RIS antenna design and the communication process. This framework simulates the entire communication pipeline, encompassing signal generation, modulation, propagation, RIS-based radiation, signal reception, alignment, demodulation, decision, and processing. Using a QPSK-modulated signal for validation, we analyze system performance and investigate the relationship between bit error rate (BER), aperture fill time, array size, and baseband symbol frequency. The results indicate that larger array sizes and higher baseband symbol frequencies exacerbate aperture fill time effects, leading to increased BER. Furthermore, we examine BER variation with respect to signal-to-noise ratio (SNR) and propose an optimal matching-based alignment algorithm, which significantly reduces BER compared to conventional pilot-based alignment methods. This work demonstrates the entire process of RIS communication, and reveals the source of bit errors, which provides valuable insights into the design and performance optimization of RIS-assisted communication systems.