GLOSSARY OF TERMS USED IN TIME SERIES ANALYSIS OF CARDIOVASCULAR DATA

|LEVEL 0| |HOMEPAGE|

Description of energy or power of a signal as a two-dimensional funtion of both time and frequency

Time-frequency distributions, TFD(t,f), are used to study nonstationary signals: they give a spectral representation of the signal which is function of time. When the signal dynamics change slowly, and high-frequency resolution is not required, TFD are usually obtained by computing the spectrogram. When high time and frequency resolutions are needed, TFD like the Wigner-Ville or the Choi-Williams distributions are preferred.

Reference:
Cohen L (1989) Time-frequency distributions- A review Proc. of  the IEEE, 77, 941-981
Pola S et al (1996) Estimation of the power spectral density in nonstationary cardiovascular series: assessing the role of the time-frequency representations (TFR) IEEE- BME
Van Steenis HG, Tulen JH (1996) The exponential distribution applied to nonequidistantly sampled cardiovascular time series. Comput Biomed Res.