Hilbert spectra of nonlinear ocean waves

Paul A. Hwang, Norden E. Huang, David W. Wang, James M. Kaihatu

Research output: Chapter in Book/Report/Conference proceedingChapterpeer-review

3 Scopus citations

Abstract

The Hilbert-Huang transform (HHT) analysis interprets wave nonlinearity in terms of frequency modulation instead of harmonic generation. The resulting spectrum contains much higher spectral energy at low frequency and sharper drop off at high frequency in comparison with the spectra derived from Fourier-based analysis methods. The high energy level in the low-frequency components of the Hilbert spectrum seems to be consistent with the rich group structure apparent in typical ocean-wave records. For wind-generated waves, the spectral level of the Fourier spectrum is about two orders of magnitude smaller than that of the Hilbert spectrum at the first subharmonic of the peak frequency. The mean frequency of the Fourier spectrm is 20% higher than that of the Hilbert spectrum. Furthermore, the frequency of the wave groups is also more likely to be properly identified in the Hilbert spectrum than in the Fourier spectrum. The implications for ocean engineering and air-sea interaction are discussed.

Original languageEnglish
Title of host publicationHilbert-huang Transform And Its Applications
PublisherWorld Scientific Publishing Co.
Pages211-225
Number of pages15
ISBN (Electronic)9789812703347
DOIs
StatePublished - 1 Jan 2005

Fingerprint

Dive into the research topics of 'Hilbert spectra of nonlinear ocean waves'. Together they form a unique fingerprint.

Cite this