Locating a weak change using diffuse waves: Theoretical approach and inversion procedure

Vincent Rossetto (1) , Ludovic Margerin (2) , Thomas Planès (3) , Éric Larose (3)

1 LPM2C - Laboratoire de physique et modélisation des milieux condensés
2 IRAP - Institut de recherche en astrophysique et planétologie
3 Ondes et Structures

We describe a time-resolved monitoring technique for heterogeneous media. Our approach is based on the spatial variations of the cross-coherence of diffuse waves acquired at fixed positions but at different dates. The technique applies to all kind of waves, provided that waveforms can be acquired with a sampling frequency much larger than the wave frequency. To locate and characterize a weak change that occurred between successive acquisitions, we use a maximum likelihood approach combined with a diffusive propagation model. We characterize this technique, locating a weak change using diffuse waves, called LOCADIFF, with the aid of numerical simulations. In several illustrative examples, we show that the change can be located with a precision of a few wavelengths and that its effective scattering cross-section can be retrieved. We investigate how the accuracy and precision of the method depends on the number of source-receiver pairs, on the time window used to compute the cross-correlation and on the errors in the propagation model. Applications can be found in nondestructive testing, seismology, radar, and sonar location.

Mots clés: acoustic wave propagation; maximum likelihood estimation; numerical analysis

Domaines: Acoustique [physics.class-ph]; Acoustique [physics.class-ph]; Matériaux et structures en mécanique [physics.class-ph]; Matériaux et structures en mécanique [physics.class-ph]; Physique Générale [physics.gen-ph]

Vincent Rossetto, Ludovic Margerin, Thomas Planès, Éric Larose. Locating a weak change using diffuse waves: Theoretical approach and inversion procedure. Journal of Applied Physics, 2011, 109 (3), pp.034903. ⟨10.1063/1.3544503⟩. ⟨hal-00563872⟩