Evolutionary spectral analysis and the generalized Gabor expansion
نویسندگان
چکیده
In this paper, we present a connection between the discrete Gabor expansion and the evolutionary spectral theory. Including a scale parameter in the Gabor expansion, we obtain a new representation for deterministic signals that is analogous to the Wold-Cramer decomposition for non-stationary processes. The energy distribution resulting from the expansion is easily calculated from the Gabor coeecients. By choosing gaussian windows and appropriate scales, the expansion can represent narrow-band and wide-band signals, as well as their combination. As an application , we consider the masking of signals in the time-frequency space and provide an approximate implementation using the new Gabor expansion. Examples illustrating the time-frequency analysis and the masking are given.
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