Coherent Target Direction-of-Arrival Estimation Based on Aperture Expansion of Acoustic Vector Array Under Colored Noise

An array with larger aperture generally offers enhanced resolution and direction-of-arrival(DOA) accuracy.However,in the presence of spatially colored noise or coherent sources,the performances of the subspace-based estimators degrade critically.A computationally efficient coherent sources direction finding method in colored noise using two uniform linear vector sensor sub-arrays far separated but orthogonally oriented is proposed.It is based on the forward-backward average covariance matrix of the observations between two sub-arrays,the matrix is used to eliminate the effect of the spatially colored noise and de-correlate the sources coherency.Then,a so-called propagator method(PM) is employed to obtain the azimuth-elevation angle estimates without eigen-decomposition and 2D iterative searching.The proposed method combined with the disambiguation processing can improve the resolution and DOA accuracy by increasing the sensor spacing in a certain range without the computational expensive derivation of coarse reference estimates.Monte-Carlo simulations are presented to verify its effectiveness.