Research on ultrasonic signal processing algorithm based on CEEMDAN joint wavelet packet thresholding

Abstract

Considering the large reconstruction error of ensemble empirical mode decomposition (EEMD) and the loss of useful high-frequency signals, a complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) joint wavelet packet threshold processing method is proposed for processing ultrasonic non-destructive testing defect signals. The ultrasonic echo signal is decomposed using CEEMDAN to obtain a group of intrinsic mode functions (IMF). The noisy components are selected using the correlation coefficient method and the high-frequency noise components are processed using the wavelet packet threshold. After threshold processing, the IMF components and reserved IMF components are accumulated and reconstructed. Compared with the EEMD algorithm, the signal-to-noise ratio was increased by 48.03% and the root mean square error and total number of iterations were reduced by 38.77% and 33.34%, respectively. This method reduces the reconstruction error and iteration time and ensures the integrity of the signal.