Error Analysis and Ultrasonic Scattering Amplitude Estimation Using the Wiener Filter with Limited Prior Information

Abstract

In ultrasonic nondestructive evaluation (NDE), flaw characterization is inhibited by the effects of the measurement system and by acoustic noise due to non-flaw related scattering of the sound.The Wiener filter can be formulated to optimally remove the effects of the measurement system and suppress the noise; however, prior information must be available abeut the neise and flaw distributions, respectively. The objective of this research is to develop an approach for the optimal implementation of the wiener filter given prior noise information but no prior flaw information. This paper beg ins with a background section in which necessary models are formulated, previous work is discussed, and the objective of the research is restated.The estimation error is then stated and analyzed. Finally, three techniques for the optimal application of the Wiener filter with limited prior information are formulated and tested. BACKGROUND