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arXiv · 1512.04811

Entropy-based Time-Varying Window Width Selection for Nonlinear type Time-Frequency Analysis

Yae-lin Sheu·Liang-Yan Hsu·Pi-Tai Chou·Hau-tieng Wu
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Abstract

We propose a time-varying optimal window width (TVOWW) selection scheme to optimize the performance of several nonlinear-type time-frequency analyses, including the reassignment method, and the synchrosqueezing transform (SST) and its variations. A window rendering the most concentrated distribution in the time-frequency representation (TFR) is regarded as the optimal window. The TVOWW selection scheme is particularly useful for signals that comprise fast-varying instantaneous frequencies and small spectral gaps. To demonstrate the efficacy of the method, in addition to analyzing a synthetic signal, we study an atomic time-varying dipole moment driven by two-color mid-infrared laser fields in attosecond physics.

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Yae-lin Sheu, Liang-Yan Hsu, Pi-Tai Chou, Hau-tieng Wu. 2015-11-29. Entropy-based Time-Varying Window Width Selection for Nonlinear type Time-Frequency Analysis. https://doi.org/10.1007/s41060-017-0053-2

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