【摘要】 相位匹配滤波器是一组线性滤波器,它的傅里叶相位与被检测信号的傅里叶相位相等。本文阐述了相位匹配滤波器的基本原理,并根据已获得的特定路径的频散曲线完成了理论设计,实现了对小震级事件面波信号的检测。使用该相位匹配滤波器对内华达地区的18次核爆事件的面波信号进行检测并计算了面波震级,与ISC公报给出的面波震级比较,相对误差很小。证明了本设计对面波信号的检测是有效的,并且可提高小震级面波信号的信噪比。更多还原

【Abstract】 The phase-matched filters are defined as a group of linear filters in which the Fourier phase of the filter is made equal to that of a given signal.In this article,the fundamental theory of phase-matched filters is described in detail,and on the basis of the given path dispersion curve the design of phase-matched filter is finished in theory.Finally,an effective method working on weak surface wave signals is developed.To test the validity of the method,it is applied to a set of nuclear explosions occurred on the Nevada Test Site and the magnitudes of these events are estimated. From comparing the MS obtained from the method with ones reported by ISC(International Seismological Centre),it is proved that the relative error is small,the design is effective to detect surface wave signal,and the signal-tonoise rate of weak surface wave signals can be enhanced.更多还原