Covert communication over multi-user channels

Covert communication;Multi user;Multiple access channels;Broadcast channels;Relay channels;Asynchronous

Arumugam, Keerthi Suria Kumar ; Electrical and Computer Engineering Bloch, Matthieu Weitnauer, Mary Ann Davenport, Mark Pokutta, Sebastian Barry, John

University:Georgia Institute of Technology

Department:Electrical and Computer Engineering

关键词: Covert communication;    Multi user;    Multiple access channels;    Broadcast channels;    Relay channels;    Asynchronous;   

Others  :  https://smartech.gatech.edu/bitstream/1853/61256/1/ARUMUGAM-DISSERTATION-2019.pdf

美国|英语

来源: SMARTech Repository

【 摘 要 】

The objective of the proposed research is to characterize the maximum rate at which information can be transmitted reliably to a legitimate receiver over certain multi-user channels while simultaneously escaping detection from one or more adversaries. Specifically, we investigate the fundamental limits of covert communication over the following multi-user channel models — a K-user discrete memoryless multiple-access channel (MAC) monitored by a single warden, a discrete memoryless broadcast channel in which one of the receivers is a warden trying to detect the presence of a covert message, and a relay channel model in which the relay aids covert transmission amidst two non-colluding wardens each monitoring the transmitter and the relay, respectively. In all three models, we observe that the covert throughput is subject to the square-root law. Also, building upon a previous result that codeword-level asynchronism results in an improved covert throughput that circumvents the square-root law, we analyze the impact on the covert throughput as a result of symbol-level asynchronism at the receiver and the warden.