Discrete Simulated Power Law Data in the Time Domain Using the Kasdin and Walter (1992) Method Visualized with the Continuous Wavelet Transform (CWT)


This document will show graphically some discrete simulated power-law noise sequences as generated with the new program powlnsim.c on a Toshiba 1555 CDS laptop computer (380 MHz, 64 MB RAM, 4.3 GB HDD).

The results are shown below. Most interesting is to watch the noise in the time-frequency (scale) domain move towards the low-frequency end of the images (the bottom of the images). The CWTs maintain information about individual disturbances at all scales and times; compare to the Digital Spectrum Analyzer results, which are time-averaged spectra rather than time-resolved as realized in the CWTs.

Animated loop of all Continuous Wavelet Transform spectra images. (322 KB)
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Kasdin, N.J. and Walter, T. (1992), "Discrete Simulation of Power Law Noise," in Proceedings of the 1992 IEEE Frequency Control Symposium, pp. 274-283.
----- (1998), Wavelet Toolware Version 1.0, software.