Window matching in the time-frequency plane and the adaptive spectrogram

Aspects of generating spectrograms which may be used in the preliminary steps of time-frequency analysis are discussed. It is shown that the major problem with the application of the spectrogram is its nonunique nature, i.e., the use of an arbitrary window for analysis. The concept of window matching is introduced, whereby the selection of the window used for analysis depends on the instantaneous signal characteristics at the given time-frequency point under analysis. Generalized instantaneous parameters are derived and subsequently used to demonstrate how the window matching may be applied. An adaptive window-matched spectrogram is generated. Practical data results are given.<>