Covert Communications with A Full-Duplex Receiver over Wireless Fading Channels

摘要

In this work, we propose a covert communication scheme where the transmitterattempts to hide its transmission to a full-duplex receiver, from a warden thatis to detect this covert transmission using a radiometer. Specifically, wefirst derive the detection error rate at the warden, based on which the optimaldetection threshold for its radiometer is analytically determined and itsexpected detection error rate over wireless fading channels is achieved in aclosed-form expression. Our analysis indicates that the artificial noisedeliberately produced by the receiver with a random transmit power, althoughcauses self-interference, offers the capability of achieving a positiveeffective covert rate for any transmit power (can be infinity) subject to anygiven covertness requirement on the expected detection error rate. This work isthe first study on the use of the full-duplex receiver with controlledartificial noise for achieving covert communications and invites furtherinvestigation in this regard.