Covert communication with beamforming over MISO channels in the finite blocklength regime  

作　　者：Xinchun YU Yuan LUO Wen CHEN 

机构地区：[1]School of Electronic Information and Electrical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China

出　　处：《Science China(Information Sciences)》2021年第9期183-197,共15页中国科学（信息科学）（英文版）

基　　金：This work was supported by National Natural Science Foundation of China(Grant No.61871264)。

摘　　要：This paper considers beamforming techniques for covert communication over multiple input single output(MISO) channels with finite blocklength. We first show that the optimal input distribution for covert communication over complex Gaussian channels is circular symmetric complex Gaussian. By reviewing our previous results on the throughput of Gaussian random coding over additive white Gaussian noise(AWGN) channels, the achievability and converse bounds on the attainable throughput over MISO channels are analyzed. Then, the optimal beamforming strategies and their relationship with the transmitting power are thoroughly investigated in a variety of situations in terms of several types of channel state information available at both ends of the system. We reveal the fact that the maximal allowable transmit power is not constrained by covertness requirement when there is full channel information of the adversary, while there is an upper bound of the transmit power which is based on beamforming and an outage-based covertness criterion if there is only partial channel information of the adversary. Finally, numerical results are presented to show that the throughput of covert communication can be increased notably by adopting a proper beamforming strategy in MISO channels in comparison with the single antenna case.

关 键 词：BEAMFORMING circular symmetric complex Gaussian covert communication MISO channels power control 

分 类 号：TN918[电子电信—通信与信息系统]