| 摘要 |
A signal analyzer, method and memory medium for generating a time varying spectrum for input signals characterized by frequency components which change in time. The signal analyzer includes a source of a sequence of digital signals representative of an input signal, a processor coupled to the source, and a memory medium coupled to the processor. The memory medium stores a software program which is executable by the processor to compute the time-varying spectrum of the input signal. When the processor executes the software program, the processor is operable to first compute a Gabor transform (that is, a sampled short-time Fourier transform) of the digital signals to produce Gabor coefficients. The processor then computes a two dimensional auto-correlation of the Gabor coefficients to produce auto-correlation results. The auto-correlation results are then applied to a 2-dimensional fast interpolation filter to produce the time-varying spectrum, wherein the time-varying spectrum is a Gabor spectrogram. The signal analyzer may repeat the above steps n+1 times, based on the order determined by a user, and sum the results for an n order time-varying spectrum. The process more may then operate to process and/or display the time-varying spectrum.
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