Application of wavelets to ultrasonic evaluation of thickness
Joel A. Rosiene, Howard A. Sholl · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1994
Thickness evaluation of materials via ultrasound can have special requirements that make the application of wavelets desirable. The thickness information is extracted from ultrasound echoes, and it is the distance between these echoes which must be estimated. Due to typical rates involved in real-time applications, only a minimum amount of processing can be done. In this paper, the multiscale analysis induced by the wavelet transform is employed and compared against conventional techniques (matched filtering by direct and a FFT based approach) in terms of computational complexity. To meet the data rate involved, the fast wavelet transform is used in a manner to obtain the necessary position information. Steps are taken to compensate for the translation variance of the wavelet transform.