Synthetic spatial spectrum DOA estimator for two closely spaced emitters

In this paper, we propose a new estimator of DOA called synthetic spatial spectrum method (SSM). The estimator is synthesized with signal subspace projection method and noise subspace projection method, which is classical MUSIC spatial-spectra algorithm. The signal subspace projection is weighted with reciprocal of principle eigenvalue. For two closely spaced emitters, the proposed SSM efficiently makes use of all information spread in eigenvalues and eigenvecters. So it provides better resolution and estimation performance in snapshot deficient and low SNR scenario than MUSIC algorithm. Computer simulation results show that the correctness and efficiency of the new method.