Analysis of the Structural Waves Backscattered by a Spherical Shell Using the Time-frequency Method
The group velocity dispersion is easily calculated from the theoretical methods such as Resonance Scattering Theory (RST) and Sommerfeld-Waston transformation, however,its difficult to extract the dispersion from experiment. In this paper,a simulation model based on the wavenumber integration and virtual source method is adopted to simulate the experiment,the source which is a pulse is emitted and the time series of the echo signal are got from the simulation model. The Wigner-ville jointly time-frequency distribution is applied to the time series of echo signal. The group velocity can be estimated from the group delays of the successive wavepackets, because the group delay can be estimated by the first-order moment of the Wigner-ville distribution along the time series. The group velocity dispersion extracted from the simulated echo signal is compared with dispersion from the resonance scattering theory, and they coincide very well.
Xbin Liu Linhui Peng
Ocean University of China,QingDao,266100 702th Research Institute,China Shipbuilding Industry Corpor Ocean University of China,QingDao,266100
国际会议
The 10th Western Pacific Acoustics Conference(第十届西太平洋声学会议WESPAC X)
北京
英文
1-6
2009-09-21（万方平台首次上网日期，不代表论文的发表时间）