Joint Covert and Secure Communications for Intelligent Reflecting Surface (IRS)-Aided Wireless Networks

Abstract

This work investigates joint covert and secure communications via intelligent reflecting surface (IRS) in a non-line-of-sight (NLOS) wireless network in the presence of an eavesdropper and a warden. We consider a coordinator of Ben communicates with two users, where one user requires secure communication and the other seeks covert communication. An optimization problem is proposed to maximize the covert rate subject to the constraints of covert requirement, secure communication rate, amplitudes and phase shifts of reflecting elements, and transmit powers of secure and covert communications. We use the successive convex approximation(SCA) method to solve this problem. The numerical results illustrate the effectiveness of utilizing an IRS and highlight the impact of the number of reflecting elements on enhancing communication quality.