A Method for Estimating the Direction of Arrival Without Knowing the Source Number Using Acoustic Vector Sensor Arrays

Since it is difficult to obtain the number of sources accurately in practical situations, direction-of-arrival (DOA) estimation methods without the number of sources are very much needed for noncooperative targets and maritime attack-defense pairings. In this article, a DOA estimation method using acoustic vector sensors (AVSs) without a known number of sources is proposed. First, a reference matrix is introduced, and the eigenvalues corresponding to the noise of this matrix converge to 0. Next, a scanning matrix containing the scanning sources is created, and the analysis of noise power invariance is used to determine the power selection method of the scanning sources. The ordering law of the eigenvalues of the source matrix scanned at different angles is applied, and the purpose of estimating DOA without the number of sources is accomplished. The proposed algorithm is capable of performing DOA estimation in situations where the number of sources is uncertain and it does not rely on the array structure, which means it can be used for arbitrary arrays. Finally, the correctness and effectiveness of the proposed algorithm are verified by simulation and experiment.