Wavelet Analysis of Vibration Signals Part 2: Wavelet Applications
David E. Newland · The International Journal of Acoustics and Vibration · 1997
This is the second of a pair of papers on the application of wavelet theory to vibration analysis.For transient data analysis, the wavelet transform and the short-time Fourier transform (STFT) produce similar results, but wavelet transforms have computational and other advantages which may be important in particular applications.This part of the paper discusses the construction of time-frequency maps.It is shown how the harmonic wavelet transform, HWT, may be modified to improve the clarity of a time-frequency map and an example is given in which a map computed by the lapped HWT is compared with a corresponding map computed by the STFT.It is found that the windowed HWT is good for time-frequency mapping because of its flexibility and ease of use and the computational efficiency of its algorithm.