Nonstationary Signal Enhancement Using The Wavelet Transform

نویسندگان

  • Vidya Venkatachalam
  • Jorge L. Aravena
چکیده

Conventional signal processing typically involves frequency selective techniques which are highly inadequate for nonstationary signals. In this paper, we present an approach to perform time-frequency selective processing using the Wavelet Transform. The approach is motivated by the excellent localization, in both time and frequency, aaorded by the wavelet basis functions. Suitably chosen wavelet basis functions are used to characterize the subspace of signals that have a given localized time-frequency support, thus enabling a time-frequency partitioning of signals. A practical implementation scheme using lter banks is also presented , and the eeectiveness of the approach over conventional techniques is demonstrated.

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تاریخ انتشار 2007