Joint Beamforming for Simultaneous Proactive Eavesdropping and Communication

This paper designs joint communication and jamming beamforming to simultaneously provide downlink communication service and wireless information surveillance. The problem is formulated as maximizing signal-to-interference-plus-noise ratio (SINR) at communication user (CU) subject to the total power budget constraint and the successful eavesdropping constraint. The semidefinite relaxation (SDR) and Charnes-Cooper transfer are applied to reformulated the primary problem into a new convex problem. We strictly prove that there must exist rank-one solutions for the SDR problem. A zero-forcing (ZF)-based suboptimal algorithm is proposed to achieve a tradeoff between performance and complexity. Simulation results are provided to verify the proposed beamforming algorithm.