Self-Adaptive Differential Evolution-Based Inductance Optimization for Resonant Acoustic RIS in Underwater Communications

Abstract

Underwater acoustic (UWA) communication systems suffer from limited bandwidth, severe multipath fading, and high propagation loss, which significantly constrain their achievable spectral efficiency and reliability. To improve UWA communication, reconfigurable intelligent surface (RIS) acts as a promising solution to enable controllable reflection of acoustic waves. However, optimizing the configuration of RIS in UWA systems is challenging due to hardware constraints, signal dispersion, and the dynamic environment. To address these challenges, this paper proposes an optimization framework for an RIS-assisted UWA system using self-adaptive mutation differential evolution (SaMDE) to maximize the achievable spectral efficiency. Specifically, the SaMDE algorithm is employed to search for the optimal RIS configuration for each element by integrating multiple mutation strategies and adaptive parameter control. Simulation results under an UWA environment generated using the Bellhop ray-tracing model demonstrate that the framework significantly improves spectral efficiency compared to several baseline approaches.