A new Nystrom approximation based efficient coherent DOA estimator for radar applications

In this work, we present a new method for the direction-of-arrival (DOA) estimation of coherent sources using the symmetric uniform linear array (ULA) without prior source number information. The proposed method constructs a new cost function based on the joint diagonalization structure of the Toeplitz matrix. The estimation of DOAs is made by developing a new spatial spectrum via a 1-D search. Furthermore, we exploit the Nystrom method to diminish the computational complexity of the proposed method. The efficacy of the new estimator is theoretically investigated and the complexity of the computation is also addressed. To examine the efficacy of the proposed method, various experiments are conducted and comparisons with the recent methods are carried out. (C) 2020 Elsevier GmbH. All rights reserved.