Time Delay Estimation Based on Wiener Filer in Ultrasonic Detection of Sediments in Drilling Hole

The normal method of measuring sediments thickness in drilling hole base on ultrasonic is to measure the sound time and intensity of echo signal. This paper presents a new viewpoint which is to measure the sediments by estimating the ultrasonic echo´s time delay, and proposes an echo time delay estimation method based on Wiener filter. Meantime, the Wiener filter is improved to make selecting of k parameter more rational. The time delay estimations under several conditions have been simulated in Matlab, and the influences of the filter parameter and noise have been analyzed. Furthermore, real echo data acquired by ultrasonic detection experiment in simulation drilling hole and sediments have been also used to estimate the real echo time delay and the result is rather good. From the computer simulation and real echo time delay estimation, Wiener filter can be applied in estimating ultrasonic echo time delay and the estimated results can aid to measure the sediments thickness later.