Analysis of dispersion of phase velocities using empirical mode frequency decomposition on SASW
No matter applying time difference or applying phase difference to extract frequency dispersion curve from single trace data for SASW, the exact information of time and phase in an arbitrary frequency in the data should be gained. Instant frequency in Hilbert transform is not limited by time frequency indeterminacy in the conventional Fourier spectrum. The empirical mode frequency decomposition (EMFD) bears not only high frequency resolution but also orthogonal behavior, instant frequency and instant phase of each intrinsic mode functions getting by EMFD arithmetic can approach the real physical frequency and physical phase (Fourier frequency and phase). For single trace seismic data, exact time frequency energy and phase diagrams can be obtained with EMFD arithmetic, more precise time frequency phase relation can be obtained by setting a threshold in time frequency energy diagrams, in order to find the true frequency dispersion curve with synchronous phase difference or asynchronous phase difference arithmetic. The numerical results indicate that the EMFD arithmetic is advanced in high time frequency phase resolution and good resistance to noise, and extracting the phase velocities by the arithmetic is very simple and effective.
empirical mode frequency decomposition intrinsic mode function Hilbert spectrum instant frequency phase velocity
Li Jiang Yixiang Xu
Institute of Geophysics and Geomatics, China University of Geosciences (Wuhan), Wuhan 430074, China Institute of Geophysics and Geomatics, China University of Geosciences (Wuhan), Wuhan 430074, China
国际会议
成都
英文
225-231
2010-06-14（万方平台首次上网日期，不代表论文的发表时间）