Optimized Sonar Broadband Focused Beamforming Algorithm

Abstract

Biases of initial direction estimation and focusing frequency selection affect the final focusing effect and may even cause algorithm failure in determining the focusing matrix in the coherent signal–subspace method. An optimized sonar broadband focused beamforming algorithm is proposed to address these defects. Initially, the robust Capon beamforming algorithm was used to correct the focusing matrix, and the broadband signals were then focused on the optimal focusing frequency by the corrected focusing matrix such that the wideband beamforming was transformed into a narrowband problem. Finally, the focused narrowband signals were beamformed by the second-order cone programming algorithm. Computer simulation results and water pool experiments verified that the proposed algorithm provides a good performance.

Underwater target passive acoustic localization method based on Hanbury Brown–Twiss interference

“…Moreover, the uncertainty of the sound field environment significantly affects positioning performance (Bucker, 1976; Tran and Trinh, 2017; Worthmann et al , 2017; Byun et al , 2020). Finally, BF applied in the field of underwater passive localization usually assumes that the received signal is a spherical wave, which has high localization accuracy for near-field hydroacoustic targets (Somasundaram and Parsons, 2011; Somasundaram, 2012; Bi et al , 2017; Yuan et al , 2020). However, with an increase in the distances between the targets, the received signal model approaches the plane wave from the spherical wave, which significantly reduces the performance of the target distance estimation.…”