Abstract:

The actual laser Doppler velocimetry signal mixed up much noise, so it was difficult to find the required Doppler frequency shift. In this paper, a wavelet packet global threshold denoising method was proposed to solve this problem, which was also used to process Doppler velocimetry signal in MATLAB. According to the characteristics of the Doppler signal, through the selection of wavelet packet decomposition scale, the comparison of threshold estimation methods and the adjustment of threshold thr, the developed method could quickly and effectively eliminate the noise signal, improve the SNR and obtain useful signals.

Key words: global threshold de-noising, SNR, Doppler frequency shift, decomposition scale