Analysis of the acoustic signal backscattered by a multi-layer structure with the spectrogram and the wavelet time-frequency methods

Mostafa Laaboubi (1) , Elhoucein Aassif (1) , Rachid Latif (2) , Gerard Maze (3) , Ali Moudden (4) , Azzedine Dliou (2) , I. Aboudaoud (1)

1 LMTI
2 ESSI ENSA
3 LOMC - Laboratoire Ondes et Milieux Complexes
4 Ecole Supérieure de Technologie

This study is to discuss the efficiency of two different methods, time-frequency representations and frequency spectral method, by comparing their ability to analyse experimentally received signals backscattered by two types of multilayer structures. We will present a study of the propagation of acoustic waves backscattered by two multilayer structures with a resonant plate "aluminum or glass" and a less resonant plate "plexiglas" separated by a water layer. The backscattering experiments have been performed in a water immersion tank. The wavelet transform and the spectrogram time-frequency representations are used in this work. The images obtained by these representations are compared to the frequency spectral method. The results obtained by the time-frequency analysis are interesting.

Mots clés: Acoustic signal; Time-frequency; Spectrogram; Wavelet transform; Frequency spectral; Multilayer structures

Domaines: Acoustique [physics.class-ph]; Acoustique [physics.class-ph]

Mostafa Laaboubi, Elhoucein Aassif, Rachid Latif, Gerard Maze, Ali Moudden, et al.. Analysis of the acoustic signal backscattered by a multi-layer structure with the spectrogram and the wavelet time-frequency methods. 10ème Congrès Français d'Acoustique, Apr 2010, Lyon, France. ⟨hal-00546826⟩