摘要
不同的波在空间的质点运动轨迹和极化方向是不同的,利用三分量或二分量记录,在特定的以t0为中心,长为N△t的滑动时窗中计算出描述波的质点运动轨迹和极化方向的特征参数。利用这些参数可以设计出合适的极化滤波函数,保留那些满足特定要求的质点运动,而衰减那些不满足设计要求的质点运动,利用某些算子可以把弹性波分解成P波和SV波,而且衰减面波;利用另外一些算子可以把P波和SV波衰减而使面波增强。这些算子甚至可以在嗓音和信号具有相同频率的情况下,成功地提高信嗓比。
The trajectories of partical motion and direction of polarization of different type of wave are different.Appling the 3-C or 2-C digital seismograms,we can calculate the parameters of the trajectories of partical motion and direction of polarization over a slidding time window of length N△t centered about t0,these parameters are calculated by covariance matrix method.Then we can design proper operators with these parameters,which preserve partical motion that satisfies specified conditions of polarization in a particular direction and attenuate partical motion that doesn't satisfy the desired criteria.Thus ,appling some operators ,we can separate the P and SV wave from elastic wave field and attenuate the surface wave.On the contrary,appling other operators,we can attenuate the P and SV wave and substract the surface wave.These operators can improve the ratio of signal to noise even though the noise has the same frequency as signal.The computation of theorietical model is perfect,which indicates the feasibility and practicability of this method.