Covert Communication with A Full-Duplex Receiver Based on Channel Distribution Information

TL;DR

This paper explores covert communication using a full-duplex receiver with only channel distribution information, proposing an optimal power design to improve performance and analyzing the impact of artificial noise.

Contribution

It introduces a novel power optimization method for covert communication with a full-duplex receiver under CDI, highlighting differences from CSI scenarios.

Findings

Optimal artificial noise power minimizes outage probability.

Performance varies with AN power due to self-interference.

Different behaviors observed under CDI and CSI assumptions.

Abstract

In this work, we consider a system of covert communication with the aid of a full-duplex (FD) receiver to enhance the performance in a more realistic scenario, i.e., only the channel distribution information (CDI) rather than channel state information (CSI) is known to a warden. Our work shows that transmitting random AN can improve the covert communication with the infinite blocklength. Specifically, we jointly design the optimal transmit power and AN power by minimizing the outage probability at Bob, and we find that the outage probability decreases and then increases as the maximum allowable AN power increases. Intuitively, once AN exceeds an optimal value, the performance will become worse because of the self-interference. The simulation results also show that the performance behaviors of CDI and CSI are different. When Willie only knows CDI, there is an optimal AN power that minimizes Bob's outage probability. However, when Willie knows CSI, the outage probability monotonically decreases with AN power.