Electromagnetic-Communication Joint Modeling and Application for RIS-Assisted Wireless Systems

Abstract

Current reconfigurable intelligent surface (RIS) modeling approaches typically isolate electromagnetic antenna design from communication system analysis, thereby failing to capture the intricate characteristics or observe real signal dynamics of RIS-assisted communication; consequently, the aperture transit effect cannot be examined neither qualitatively nor quantitatively. To bridge this gap, this article proposes a comprehensive end-to-end simulation framework that jointly models physical RIS antenna behavior and the complete signal processing chain. The proposed model accounts for actual crosstalk between element links, achieving higher fidelity and realism. Validating with quadrature phase-shift keying (QPSK), this study visualizes signal evolution and quantitatively analyzes the impact of the aperture transit effect on system performance. Experiments conducted on a 2 GHz RIS system with a fixed signal-to-noise ratio (SNR) of 10 dB demonstrate that larger array dimensions, higher symbol rates, and wider emission angles significantly exacerbate this effect, leading to severe inter-symbol interference (ISI) and bit error rate (BER) degradation. By characterizing the BER as a function of SNR under various configurations, this work identifies the aperture transit effect as a fundamental source of intrinsic errors, providing essential guidelines for the design and optimization of future wideband RIS-assisted systems.