Pair-Matching Method by Signal Covariance Matrices for 2D-DOA Estimation

The two-dimensional direction-of-arrival (2D-DOA) estimation for the L-shaped array is usually divided into two one-dimensional DOA (1D-DOA) estimation for the two linear subarrays, and then the elevation and azimuth angles are obtained from the two correctly matched 1D-DOAs. This letter presents a novel method for pair-matching of the two 1D-DOAs. The key points of the proposed method are: 1) construct two signal covariance matrices corresponding to the two estimated 1D-DOAs; 2) introduce an objective function, defined over the two signal source covariance matrices, to find the matched 1D-DOAs; 3) by introducing a permutation matrix for the signal covariance matrices, the optimal pair-matching is obtained with an efficient method. Simulations under different scenarios, with low signal-to-noise ratio (SNR), snapshot deficiency, and uncorrelated or coherent signal settings, show the robustness of the proposed method.