Multiplane deconvolution in underwater acoustics: Simultaneous estimations of source level and position

Maxime Polichetti,Valentin Baron,Barbara Nicolas,Jérôme I Mars

doi:10.1121/10.0005513

Abstract

In many acoustic imaging applications, conventional beamforming (CBF) cannot provide both accurate position and source level estimates simultaneously. Also, the CBF acoustic maps suffer from many artifacts due to the spreading of large point-spread-functions. An original CLEAN deconvolution procedure, including an additional plane containing out-of-plane interfering sources, is proposed here to achieve simultaneous localization, source level estimation, and de-noising. The approach is illustrated using experimental data mimicking a challenging deep-sea mining configuration: an underwater acoustic source of interest is located 700 m below the sea surface, tens of meters from a 3 m-length array, with boat noise as the disturbing source.

Highlights

Acoustic imaging generally follows a common scenario: a source of interest has to be located on an imaging plane using an acoustic array of microphones, and a strong disturbing source interferes with it, deteriorating the acoustic maps and preventing characterization of the source of interest
The present study addresses acoustic imaging with an original strategy applied to the specific context of underwater deep-sea mining
Note that the source level estimate ranking is changed due to the compensation with d02ð~r Þ: the first detected maximum [red cross in Fig. 2(a)] has been erroneously interpreted by CLEAN-SC as resulting from a source located in the source plane

Summary

Introduction

Acoustic imaging generally follows a common scenario: a source of interest has to be located on an imaging plane using an acoustic array of microphones, and a strong disturbing source (possibly out-of-plane) interferes with it, deteriorating the acoustic maps and preventing characterization of the source of interest (e.g., position, level, spectrum estimation). (Kuperman and Roux, 2007) Many parameters of these acoustic sources (e.g., position, acoustic level, spectrum) are of great interest for research, defense, or industrial purposes. All these acoustic sources are likely to interfere with each other, hindering correct monitoring. In the case of acoustic imaging in deep-sea mining environments, surface boat noise is recorded by the acoustic array and prevents the estimation of both the position and level of the acoustic sources of interest on the seafloor, as it generates strong artifacts on acoustic maps (Pham et al, 2019)

Methods

Results

Conclusion