In vibration test,the signal is always along with noise.If the noise belongs to white noise,fourier transform is very suit to identify and process it,after then remove it.But when there exists low energy impact signal,traditional band pass filter remove noise and the precise position of impact signal is blured.
The time-frequency of the wavelet transform and the signal wavelet decomposition-reconstruction algorithm based on the multi-resolution analysis are analyzed.The signal local s...