A Method for the Central Direction of Arrival Estimation of Coherently Distributed Source

We consider the problem of estimating the central direction of arrival (DOA) of a coherently distributed source. In this paper, the integral steering vector of coherently distributed source is deduced to be a Schur-Hadamard product comprising point source steering vector and a real vector. And then a blind estimator based on second order statistics is proposed to estimate the central DOA without adopting any prior knowledge about the shape of angular signal intensity. The proposed method can be calculated analytically from the known signal model, so a closed-form solution to the central DOA estimation can be derived without any peak-finding searching and eigenvalue decomposition or singular value decomposition. In addition, the proposed algorithm can provide a more precise central DOA estimation using the maximum number of the second order statistics equal to the number of sensors and can give effective estimation even at low SNR. Simulation results show that the proposed method exhibits the attributes, an improved accuracy and a better robustness.