DOA estimation error reduction of correlated waves for Khatri-Rao product extended-array by using N-th root of correlation matrix

In this paper, we study on DOA estimation error reduction by nested array in the presence of correlated waves. In recent years, at simple array signal processing technique called nested array has been proposed. By using the technique, degrees-of-freedom of the array can be easily increased. However, accuracy of DOA estimation deteriorates when correlated or coherent waves arrived. Therefore, in this report, we propose a new method for error reduction by using N-th root of matrix. The optimal order N depends on the data. In this study, we also provide an iterative method to determine a sub-optimal N by using estimated correlation coefficients. Availability of the proposed method is verified by computer simulation.