Acoustic Passive Directional Method of Broadband Source Using Multiple Small Aperture Subarray

An approach for the direction of arrival (DOA) estimation of multiple broadband sources was presented by using multiple small aperture subarrays, and a novel signal model used in rank reduction estimator (RARE) was used to deal with the information from multiple small aperture subarrays. Then approximate RARE estimator was built to estimate DOA of multiple broadband sources. Source resolution and directional precision were increased by extending array aperture. Moreover, false peak that appears in the conventional methods based on eigen subspace was removed from spatial spectrum effectively with the proposed method, and sensitivity to position error was reduced by robust RARE estimator. Simulative and experimental results show that the method achieves better statistical stability and lower threshold of signal to noise ratio(SNR). Correct DOA estimation can also be obtained in the case of large intersubarray displacement error.