Passive source localization based on multipath arrival angles with a vertical line array using sparse Bayesian learning

Abstract

In deep water, multipath time delays or frequency-domain interference periods of the acoustic intensity combined with multipath arrival angles are typically used for source localization. However, depth estimate is hard to achieve for a narrowband source at a remote part of the direct arrival zone as the required bandwidth increases with the source range. In this paper, a passive source localization method with a vertical line array, suitable for both broadband and narrowband sources, is proposed. Based on the variation trends of multipath angles with source range and depth, source localization is achieved by only matching the measured angles of the direct path and surface-reflected path with model-based values of a predefined grid of potential source locations. Considering the angle resolution limited by the array aperture and the presence of coherent multipath, sparse Bayesian learning is used and compared with the conventional beamforming and the minimum-variance distortionless-response beamforming to resolve and estimate the multipath angles. Simulations and experimental data of explosive sources collected by a vertical line array in the South China Sea are carried out to illustrate the method and demonstrate the performance.

Source localization by Matching the Multipath Arrival Angles based on Sparse Bayesian Learning

“…The Gaussian kernel function is used to match multipath angles for source localization. In comparison to the literature [7] the proposed approach eliminates the need to distinguish the multipath angles from the azimuthal spectrum and demonstrates higher adaptability in complex scenarios.…”

“…By extracting the multipath characteristics from the measured signals, such as arrival angles, time delays, or interference structures, the matching the multipath arrival characteristics (MMAC) localization method exploits these mapping relationships to determine the range and depth of the source. In literature [7] a deep-sea vertical array is used to localizing the sound source. It is achieved by extracting the D path and SR path arrival angles and matching to the candidate source angles calculated by Ray model.…”