短时傅立叶变换和广义S变换用于提取面波频散曲线效果对比研究  

SHORT-TIME FOURIER TRANSFORM AND GENERALIZED S TRANSFORMATION ARE USED OF EXTRACTING RAYLEIGH-WAVE DISPERSION CURVES

作　　者：袁伟[1] 周洪生[1] 刘成东 李江鹏 张薇[1] 

机构地区：[1]成都理工大学地球探测与信息技术教育部重点实验室,成都610059 [2]中冶成都勘察研究院有限公司,成都610023 [3]四川鑫瑞志工程检测有限公司,成都610071

出　　处：《物探化探计算技术》2013年第1期54-59,3,共6页Computing Techniques For Geophysical and Geochemical Exploration

摘　　要：瑞雷面波勘探作为一种无损原位检测方法,已越来越多的应用于岩土工程测试与环境工程中,其中频散曲线的提取则是得到面波速度的重要一步。这里将短时傅里叶变换与广义S变换两种线性时～频分析方法用于瑞雷面波的频散曲线提取,并加以对比分析它们的应用效果。通过理论模型与实际地震记录分析得出:①短时傅里叶变换只能对浅部能量较强的高频部份的瑞雷面波的频散曲线提取效果较好,而对低频能量较弱的部份提取效果则不佳;②广义S变换通过λ和p两个参数的引入,使其能根据信号频率的高低自动调解窗函数的形态与大小,具有多分辨的特性,使其同时对高频、低频的瑞雷面波信号有更好的处理效果,从而有利于提高瑞雷波的勘探深度。Rayleigh wave exploration as a non-destructive in situ detection method has been increasingly used in geotechnical engineering testing and environmental engineering.Extraction of dispersion curves is an important step in the surface wave velocity.This will be short-time Fourier transform and the generalized S transform two linear time-frequency analysis method for Rayleigh wave dispersion curve extraction.According to the analysis of the theoretical model and real seismic data,it is concluded that:①Short-time Fourier transform only {or shallow high-frequency part of the energy of strong Rayleigh wave dispersion curve extraction is better,while the low-frequency energy extraction is the weaker part of the poor.②Generalized S transform λ and p by the introduction of two parameters to the signal frequency according to the level of automatic mediation shape and size of the window function,with multi-resolution features,so while the high and low frequency of the Rayleigh wave signal better treatment effect,and thus help to improve the exploration depth of the Rayleigh wave.

关 键 词：广义S变换 短时傅里叶变换 瑞雷波 频散曲线提取 

分 类 号：O174.22[理学—数学]