Intelligent Reflecting Surface (IRS)-Aided Covert Wireless Communications With Delay Constraint

This work examines the performance gain achieved by deploying an intelligent reflecting surface (IRS) in covert communications. To this end, we formulate joint design of transmit power and IRS reflection coefficients taking into account communication covertness for cases with global channel state information (CSI) without a warden’s instantaneous CSI. For case CSI, first prove that perfect is achievable aid even single-antenna transmitter, which impossible IRS. Then, develop penalty successive convex approximation (PSCA) algorithm to tackle problem. Considering high complexity PSCA algorithm, further propose low-complexity two-stage where analytical expressions IRS’s are derived. derive constraint analytically facilitating optimal phase shift design. consider three hardware-related constraints on amplitudes determine their designs together power. Our examination shows significant can be