Abstract
In the analysis of time-varying signals various functions of time and frequency are used in order to describe the signal as a composition of several frequency bands with varying contributions to the intensity of the signal. For some of them, e.g. the spectrogram, a trade-off has to be made between spectral and temporal resolution. For others, e.g. the complex energy-density function, the interpretation is complicated and confusing. Another function of time and frequency, the Wigner distribution of the analytic signal, lacks both these undesirable properties. The lucid and transparent way in which this real function displays the temporal as well as the spectral characteristics of a real signal, make it a powerful tool in the analysis of time-varying physiological signals.
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Hermes, D.J. Separation of time and frequency. Biol. Cybern. 52, 109–115 (1985). https://doi.org/10.1007/BF00364001
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DOI: https://doi.org/10.1007/BF00364001