Research on an accurate passive location algorithm based on the underwater target acoustic-magnetic fusion in the near field

Abstract

The passive localization of the underwater target is conducive to accurately track the underwater target and obtain their radiation characteristics. While, in practical application, the algorithm is affected by many uncertain factors. Such as the target strength, complex shallow water environment, input parameters and so on. So, the robustness of ultra-short-range localization performance is relatively poor. The passive location algorithm of magnetic field based on field modeling and optimized search method is not affected by the adverse factors such as shallow water environment and acoustic array. It can achieve high-precision location performance. The location accuracy is about 0.1 time of the ship’s length. However, due to the influence of the fast attenuation of magnetic field, this algorithm can only realize the precise positioning of ultra-short-range and high stability according to the magnitude of magnetic field. This paper attempts to take advantage of the focused beamforming location algorithm and magnetic field high robustness positioning algorithm for the first time. And the adaptive filtering algorithm is adopted to effectively process the passive localization of acoustic and magnetic field results, so as to overcome the adverse effect of the conical ambiguity surface of scalar acoustic array on focused beamforming acoustic image passive location algorithm, and realize high precision and high stability passive localization results of the ship in near-field online.