High-frequency Total Focusing Method (TFM) imaging in strongly attenuating materials with the decomposition of the time reversal operator associated with orthogonal coded excitations

E.L. Villaverde (1) , S. Robert (1) , C. Prada (2)

1 DISC - Département Imagerie et Simulation pour le Contrôle
2 ESPCI Paris - Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris

In the present work, the Total Focusing Method (TFM) is used to image defects in a High Density Polyethylene (HDPE) pipe. The viscoelastic attenuation of this material corrupts the images with a high electronic noise. In order to improve the image quality, the Decomposition of the Time Reversal Operator (DORT) filtering is combined with spatial Walsh-Hadamard coded transmissions before calculating the images. Experiments on a complex HDPE joint demonstrate that this method improves the signal-to-noise ratio by more than 40 dB in comparison with the conventional TFM.

Domains: Physics [physics]

E.L. Villaverde, S. Robert, C. Prada. High-frequency Total Focusing Method (TFM) imaging in strongly attenuating materials with the decomposition of the time reversal operator associated with orthogonal coded excitations. 43RD ANNUAL REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION, Jul 2016, Atlanta, United States. pp. 040002, ⟨10.1063/1.4974589⟩. ⟨cea-01811888⟩