Localization of a small change in a multiple scattering environment without modeling of the actual medium

Sandrine Rakotonarivo (1) , S.C. Walker (1) , W. A. Kuperman (1) , Philippe Roux (2)

1 Marine Physical Laboratory of the Scripps Institution of Oceanography
2 ISTerre - Institut des Sciences de la Terre

A method to actively localize a small perturbation in a multiple scattering medium using a collection of remote acoustic sensors is presented. The approach requires only minimal modeling and no knowledge of the scatterer distribution and properties of the scattering medium and the perturbation. The medium is ensonified before and after a perturbation is introduced. The coherent difference between the measured signals then reveals all field components that have interacted with the perturbation. A simple single scatter filter (that ignores the presence of the medium scatterers) is matched to the earliest change of the coherent difference to localize the perturbation. Using a multi-source/receiver laboratory setup in air, the technique has been successfully tested with experimental data at frequencies varying from 30 to 60 kHz (wavelength ranging from 0.5 to 1 cm) for cm-scale scatterers in a scattering medium with a size two to five times bigger than its transport mean free path.

Mots clés: Acoustic wave scattering; Acoustic Signal Processing

Domaines: Acoustique [physics.class-ph]

Sandrine Rakotonarivo, S.C. Walker, W. A. Kuperman, Philippe Roux. Localization of a small change in a multiple scattering environment without modeling of the actual medium. Journal of the Acoustical Society of America, 2011, 130, pp.3566. ⟨10.1121/1.3652859⟩. ⟨hal-01237329⟩