Cooperative Jamming and Relay Selection for Covert Communications

TL;DR

This paper explores how cooperative jamming and relay selection can enhance covert communication in wireless systems, providing theoretical models and simulations to optimize covert rates against detection.

Contribution

It introduces two relay selection schemes with cooperative jamming, models their covert rate performance, and optimizes power control for improved covertness.

Findings

Theoretical models accurately predict covert rate performance.

Max-min relay selection outperforms random relay selection.

Optimized power control significantly enhances covert communication.

Abstract

This paper investigates the covert communications via cooperative jamming and relay selection in a wireless relay system, where a source intends to transmit a message to its destination with the help of a selected relay, and a warden attempts to detect the existence of wireless transmissions from both the source and relay, while friendly jammers send jamming signals to prevent warden from detecting the transmission process. To this end, we first propose two relay selection schemes, namely random relay selection (RRS) and max-min relay selection (MMRS), as well as their corresponding cooperative jamming (CJ) schemes for ensuring covertness in the system. We then provide theoretical modeling for the covert rate performance under each relay selection scheme and its CJ scheme and further explore the optimal transmit power controls of both the source and relay for covert rate maximization. Finally, extensive simulation/numerical results are presented to validate our theoretical models and also to illustrate the covert rate performance of the relay system under cooperative jamming and relay selection.