Two-Dimensional Direction-of-Arrival Estimation Based on Augmented Lagrange Multiplier for Multiband Integrated Sparse Array

To achieve underdetermined 2-D DOA estimation of signals in different band, a novel integrated sparse array based on four rectangular sparse subarrays with reduced coupling effect and a 2-D DOA estimator via matrix completion are proposed. Firstly, the concept of original rectangular uniform array (ORUA) is proposed and the nested Toeplitz characteristic of covariance matrix is analysed. Then nested Toeplitz covariance matrix is estimated quickly by augmented Lagrange multiplier. Based on the precisely estimated covariance matrix, we achieve 2-D DOA estimation with unitary-ESPRIT. Simulation results demonstrate that our proposed algorithm can achieve superior 2-D DOA estimation performance and high estimation accuracy.