A Comparison of the Energy Flux Computation of Shoaling Waves Using Hilbert and Wavelet Spectral Analysis Techniques
نویسندگان
چکیده
Fourier-based spectral analysis methods have been widely used for studying random waves. One major weakness of the Fourier-based spectral analysis methods is the assumption of linear superposition of wave components. As a result, the energy of a nonlinear wave is spread into many harmonics, which are phase-coupled via the nonlinear dynamics inherent in nearshore wave propagation. In addition to the nonlinearity issue, strictly speaking Fourier spectral analysis should be used for periodic and stationary processes only. Wave propagation in inhomogeneous near shore regions is certainly neither stationary nor periodic.
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