Efficient DOA Estimation Method for Reconfigurable Intelligent Surfaces Aided UAV Swarm

The conventional direction of arrival (DOA) estimation methods are performed with multiple receiving channels. In this paper, a changeling DOA problem is addressed in different scenario only one full-functional channel. A new unmanned aerial vehicle (UAV) swarm system using lifted reconfigurable intelligent surface (RIS) proposed for the estimation. UAV movement degrades performance significantly, and existing atomic norm minimization (ANM) cannot be used array perturbation. Specifically, considering position perturbation UAVs, norm-based method proposed, where an defined parameter Then, customized semi-definite programming (SDP) derived to solve method, from traditional SDP additional transforming matrix formulated. Moreover, gradient descent applied refine estimated further. Simulation results show that achieves much better RIS-aided channel than various benchmark schemes.