Low-complexity Method for the Central DOA Estimation  of Coherently Distributed Sources

The traditional methods for the direction-of-arrival (DOA) estimation of coherently distributed (CD) sources generally need perform a grid searching or the eigendecomposition of the high-dimensional sample covariance matrix, and the computational complexities of them are obviously higher. Aiming at the problem mentioned above, this paper proposes a low-complexity estimation method for the central DOA of CD sources by using uniform linear array (ULA). The proposed method estimates the central DOAs of distributed sources by combining the rotational invariance property of shifted array with propagator method. The method need not any peak-finding searching and the eigendecomposition of the sample covariance matrix, thus it provides a lower computational complexity compared to the classical subspace methods. The method has good estimation performance under small angular spread condition and its performance approaches greatly distributed signal parameter estimator (DSPE) algorithm. And it is also a blind estimator, which does not depend practically on the specific angular distribution shapes of distributed sources. Simulation results show that the proposed method is effective.