Direction-of-arrival estimation based on spatial–temporal statistics without knowing the source number

• An algorithm for finding DOAs of multiple temporally correlated signals is devised.
• The proposed algorithm does not require the source number a priori.
• The well-known MUSIC method is a special case of the proposed algorithm.
• It is superior to conventional subspace-based DOA estimators.

Direction-of-arrival (DOA) estimation is a central problem in array processing and has a variety of applications. In this paper, a new algorithm for finding DOAs of multiple temporally correlated signals is devised. The proposed approach is based on the joint diagonalization structure of a set of spatio-temporal correlation matrices. Unlike the subspace-based DOA estimators, it is not necessary to estimate the noise or signal subspace explicitly. Moreover, the proposed method can provide the spatial spectrum and estimate the DOAs even when the number of sources is not known a priori. Interestingly, it is revealed that the well-known MUSIC method is a special case of our algorithm. Simulation results validate that the developed approach is superior to conventional DOA estimators in terms of resolution capability, estimation accuracy, and robustness against array model errors.