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  • Research Article
  • Open Access

Instantaneous Spectrum Estimation from Event-Based Densities

  • 1Email author,
  • 2,
  • 3 and
  • 4
EURASIP Journal on Advances in Signal Processing20022002:180621

  • Received: 31 July 2001
  • Published:


We present a method for obtaining a time-varying spectrum that is particularly suited when the data are in event-based form. This form arises in many areas of science and engineering, and especially in astronomy, where one has photon counting detectors. The method presented consists of three procedures. First, estimating the density using the kernel method; second, highpass filtering the manifestly positive density; finally, obtaining the time-frequency distribution with a modified Welch′s method. For the sake of validation event-based data are generated from a given distribution and the proposed method is used to construct the time-frequency spectrum and is compared to the original density. The results demonstrate the effectiveness of the method.


  • time-frequency analysis
  • density estimation
  • kernel method

Authors’ Affiliations

Dipartimento di Elettronica, Politecnico di Torino, Duca degli Abruzzi 24, Torino, 10129, Italy
City University of New York, 695 Park Avenue, New York, NY 10021, USA
US Department of Defense, Fort Meade, MD 20755, USA
Space Science Division, NASA Ames Research Center, Moffett Field, CA 94035, USA


© Galleani et al. 2002