Robust Secure Beamforming in MISO Full-Duplex Two-Way Secure Communications

• Published in: IEEE transactions on vehicular technology Vol. 65; no. 1; pp. 408 - 414
• Main Authors: Feng, Renhai, Li, Quanzhong, Zhang, Qi, Qin, Jiayin
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.01.2016; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Algorithms; Array signal processing; Beamforming; Channel estimation; Channels; Communication systems; Computer simulation; Degradation; Full-duplex; multiple-input-single-output (MISO); Optimization; Receiving antennas; Robustness; secure communications; Transforms; two-way; Uncertainty; worst-case model; worst-case model; Full duplex; secure communications; two way; multiple-input–single-output (MISO)
• ISSN: 0018-9545; 1939-9359
• DOI: 10.1109/TVT.2015.2394370

Considering worst-case channel uncertainties, we investigate the robust secure beamforming design problem in multiple-input-single-output (MISO) full-duplex, two-way secure communications. Our objective is to maximize worst-case sum secrecy rate under weak secrecy conditions and individual transmit power constraints. Since the objective function of the optimization problem includes both convex and concave terms, we propose to transform convex terms into linear terms. We decouple the problem into four optimization problems and employ the alternating optimization algorithm to obtain the locally optimal solution. Simulation results demonstrate that our proposed robust secure beamforming scheme outperforms the nonrobust one. It is also found that when the regions of channel uncertainties and the individual transmit power constraints are sufficiently large, because of self-interference, the proposed two-way robust secure communication is proactively degraded to one-way communication.