Covert Communication for Multi-Channel Transmission with A Full-Duplex Receiver

This article considers a covert wireless communication (CWC) scheme for multi-channel wireless transmission systems with a full-duplex receiver. Specifically, the transmitter randomly selects a sub-channel from multiple available channels to send information in each individual slot and tries to ensconce its transmission behavior from a warden. We deduce the closed-form expressions of the detection error probability (DEP) at the warden and the transmission outage probability (TOP) at Bob under fading channels. Then, we maximize the effective covert rate (ECR) and we provide the guidance of the optimal transmit power under a certain covert constraint. Numerical results show that, by comparing with the single-channel transmission scheme, the proposed multi-channel wireless transmission scheme significantly confuses warden's detection, and thus improves the ECR.