Measuring Time-Frequency Distributions Concentration
نویسنده
چکیده
Efficient measurement of time-frequency distributions (TFDs) concentration can provide a quantitative criterion for evaluation of various distributions performance. It can be used for adaptive and automatic parameter selection in time-frequency analysis, without supervision of a user. Measures for distribution concentration of monocomponent signals date back to [3], [8]. For more complex signals, some quantities from statistics and information theory were the inspiration for defining measures of the TFDs concentration [4][5]. They provided good quantitative measure of the auto-terms concentration. Various and efficient modifications are used in order to take into account the appearance of oscillatory cross-terms. The application of concentration measures will be demonstrated on automatic determination of the “best window length” for the spectrogram or “the best number of terms” in the method that provides transition form the spectrogram toward the pseudo Wigner distribution (pseudo WD) [Article 6.2].
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