Time-frequency localization operators of Cohen’s class

  • Jayakumar Ramanathan
  • Pankaj Topiwala
Chapter
Part of the NATO ASI Series book series (ASIC, volume 442)

Abstract

A technique of producing signals whose energy is concentrated in a given region of the time-frequency plane is examined. The degree to which a particular signal is concentrated is measured by integrating a time-frequency distribution over the given region. This procedure was put forward by Flandrin, and has been used for time-varying filtering in the recent work of Hlawatsch, Kozek, and Krattenthaler. In this paper, the operators associated with the Wigner distribution and the spectrogram are considered. New results on the decay rate of the eigenvalues and the smoothness and decay of the eigenfunctions are presented.

Keywords

Localization Operator Wigner Distribution Hermite Function Weyl Correspondence Signal Energy Concentration 
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Copyright information

© Springer Science+Business Media Dordrecht 1994

Authors and Affiliations

  • Jayakumar Ramanathan
    • 1
  • Pankaj Topiwala
    • 2
  1. 1.Department of MathematicsEastern Michigan UniversityYpsilantiUSA
  2. 2.Mail Stop E025MITRE Corp.BedfordUSA

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