RIS-Aided Covert Communications with Statistical CSI: A Multiport Network Theory Approach

TL;DR

This paper introduces a new RIS-aided covert communication framework using multiport network theory, accounting for mutual coupling and structural scattering, with limited channel knowledge, validated by numerical results.

Contribution

It presents a novel modeling approach for RIS in covert communications considering practical effects and limited channel information, advancing the state-of-the-art.

Findings

Successful covert communication under covertness constraints

Effective modeling of RIS with mutual coupling and scattering effects

Numerical validation demonstrating practical feasibility

Abstract

A novel framework for covert communications aided by Reconfigurable Intelligent Surfaces (RIS) is proposed. In this general framework, the use of multiport network theory for modelling the RIS consider various aspects that traditional RIS models in communication theory often overlook, including mutual coupling between elements and the impact of structural scattering. Moreover, the transmitter has only limited knowledge about the channels of the warden and the intended receiver. The proposed approach is validated through numerical results, demonstrating that communication with the legitimate user is successfully achieved while satisfying the covertness constraint.