Two-Dimensional DOA Estimation Based on Programmable Sparse Metasurface

In this paper, the two-dimensional (2-D) programmable sparse metasurface (PSM) is constructed, and the direction of arrival (DOA) estimation algorithm based on it is proposed. The rows of the programmable metasurface are located with spacings according to a sparse sequence, then the equivalent covariance matrix of an uniform metasurface with more virtual patches is constructed, which improves the estimated number of 2-D DOAs and the DOA estimation accuracy. The simulation results show that the performance of the proposed PSM is almost equal to that of the uniform metasurface with greater number of rows of patches.