Robust Beamforming for Secure and Covert Communications Against Location Uncertainty

Manlin Wang, Tian Liu, Ouxin Lu, Di Wang, Bin Xia

Abstract: The security of air-to-ground communication is seriously challenged by the malicious eavesdropper/warder. Beamforming technology with multiple antennas can achieve signal enhancement/nulling in specific direction to improve transmission security. However, the inaccurate location information weakens the ability of existing beamforming schemes to guarantee security. To address this issue, in this work, a robust beamforming scheme is proposed for secure and covert communication, where the receiver and the eavesdropper/warder are potentially located within some regions. In particular, the system performance is analyzed, including the secrecy rate and the detection error probability. In addition, to maximize the secrecy rate, an optimization problem is formulated with location uncertainty. Further, the bound for the uncertainty region is derived, and the lossy $\mathcal {S}$ -procedure is exploited for solving the problem. Numerical results demonstrate the superiority of the proposed scheme in terms of the covertness performance and the secrecy rate. Besides, increasing the number of antennas does not always lead to performance gains under the scenario with location uncertainty.

External IDs:dblp:journals/wcl/WangLLWX25