OMNIPHONE检波器的问题分析与改造

ＯＭＮＩＰＨＯＮＥ是一种带有微处理器的三分量智能型检波器，它具有极化滤波的能力．笔者对该检波器进行了全面的分析与介绍，指出了ＯＭＮＩＰＨＯＮＥ检波器的成功之处．未经改造的ＯＭＮＩＰＨＯＮＥ检波器存在以下问题：（１）水平两个分量间串扰严重，串扰值大于０ｄＢ；（２）水平两个分量对理想圆形面波的压制能力不够，压制比为－１０ｄＢ～１０ｄＢ．经过对ＯＭＮＩＰＨＯＮＥ检波器软硬件的综合分析，发现存在以下缺陷：（１）随着分析信号频率的升高（１０Ｈｚ～２５０Ｈｚ），Ｕ、Ｖ、Ｗ三个分量间由于采样时延引起的相移逐步加大；（２）软件编制过程中，坐标旋转（从加尔彼林坐标变换到直角坐标）部分存在错误．针对以上缺陷，改正了软件编制过程中存在的错误，并减小了三分量间的采样时延．改造后测试结果表明：ＯＭＮＩＰＨＯＮＥ三分量间串扰显著减小，对理想圆形面波的压制能力增强，三个分量的频率响应曲线更加平坦．

Analysis and Improvement of OMNIPHONE—a Three Component Digital Geophone

OMNIPHONE is an intelligential three component geophone with a microprocessor.It can attenuate surface wave with a polarization filter.This paper introduces OMNIPHONE and analyses its advantages.But it has also two disadvantages :(1)There is interference between two horizontal components(radial and tangential);(2)Two horizontal components cant effectively attenuate surface wave.For this reason,the authors analysed the software and hardware of OMNIPHONE,and found two drawbacks in them:(1)the phase differences caused by sampling time interval(250 microseconds)between three components increase with the increase of the frequencies of analysed signals;(2)in the software,there is a mistake of conversion from Galperin coordinate system to Cartesian coordinate system.After the mistake is corrected and the sampling time interval is reduced to 60 microseconds,the improved OMNIPHONE can effectively attenuate surface wave,the interference between two horizontal components is greatly decreased,and the frequency response curves of three components become more even.