FAST APPROXIMATION OF TIME-FREQUENCY REPRESENTATIONS AT ARBITRARY FREQUENCIES

Fast approximation algorithms for the short-time Fourier transform, sh ort-time Hartley transform and pseudo-Wigner distribution are develope d as analysis tools of time-frequency spectra at arbitrary frequencies . Under some specified error level, these algorithms retain the effici ency of fast Fourier, or fast Hartley transform computation. This prov ides the time-frequency spectral analysis of nonstationary signals a m ore general and flexible method to compute the time-varying spectra ea sily and quickly. (C) 1998 Elsevier Science B.V, All rights reserved.