三种非平稳信号时频分析的方法 窗口傅里叶变换、wigner分布和小波变换-Three non-stationary time-frequency analysis window Fourier transform, wigner distribution and wavelet transform

一种新的傅里叶分析方法，自适应傅里叶分析-A new method of fourier analysis, adaptive fourier analysis

　Ext rapolation operator of one2way wave field has great application in seismic migration imaging. According to their implement , these operators can be classified into three kinds : Kirchhoff integral method , implicit definite difference in spa