DOA Estimation based on Sparse Representation of Covariance Matrix for 4- D Antenna Arrays

In this paper, Direction Of Arrival (DOA) estimation algorithm based on sparse representation of covariance matrix for four dimensional (4-D) antenna arrays with unknown source number is proposed to solve defect that DOA estimation needs to know source number in existing DOA estimation algorithms for 4-D antenna arrays. The algorithm represents sparse representation of covariance matrix for 4-D antenna arrays directly. The whole sparse reconstruction process does not need to know source number. Simulation results show that the algorithm can achieve accurate DOA estimation under unknown source number, low SNR, closely spaced signals and coherent signals.