Ultrasonic Signal Denoising Based on a New Wavelet Thresholding Function

摘要

In the ultrasonic nondestructive testing, the echo signal is polluted by noise and the signal-to-noise ratio is low. To solve the problem, a new wavelet thresholding function is introduced in this paper based on soft and hard thresholding functions. Compared with the existing improved thresholding functions, the new thresholding function is simple in computation and continuous and easy to adjust, it is suitable for some kinds of mathematical disposals. The simulation results show that the new thresholding function can suppress the noise effectively, it is better than soft and hard thresholding functions and the existing improved thresholding functions and has high practical value.