Robust Secure Beamforming for Cognitive Satellite Aerial Networks with UAV Jittering

This paper designs a robust secure beamforming to combat UAV jittering in a cognitive satellite aerial network. Considering deterministic angular uncertainty model, we formulate a worst-case secrecy rate maximization problem subject to the transmit power constraint and the interference limit for a primary satellite earth station. To solve this non-convex problem, we derive a second-order Taylor series expansion-based approach to approximate the complex trigonometric form in terms of angular jitter errors into a quadratic one. Based on this result, we transform the original non-convex problem into a convex one by employing S-Procedure and propose an iterative penalty function-based successive convex approximation algorithm to achieve the sub-optimal solution. Simulation results are presented to confirm the robustness and superiority of the proposed robust BF scheme.