模拟与数字检波器记录精度对比及其对信噪比的影响  

Comparison of recording accuracy between analog geophone and MEMS accelerometer and their influence to the S/N ratio

作　　者：魏继东[1] Wei Ji-dong(Geophysical Corporation Shengli Branch,SINOPEC,Shandong Dongying 257086,China)

机构地区：[1]中国石化石油工程地球物理公司胜利分公司,山东东营257086

出　　处：《地球物理学进展》2018年第4期1726-1733,共8页Progress in Geophysics

基　　金：中国石化石油工程地球物理公司"高精度地震资料拓展频率方法研究"项目(2017-02-01)资助

摘　　要：动圈式模拟检波器与MEMS数字检波器是当前地震勘探野外采集中非常具有代表性的两种检波器,前者的典型代表是20DX,是无源检波器;后者的典型代表是法国Sercel公司生产的DSU系列,是有源检波器.在经由地震仪采集地震信号的时候,20DX产生的模拟电信号由A/D转换器完成模数转换,由地震仪记录到磁带上;DSU系列则借助检波器自身的ASIC芯片完成模数转换.由于以上转换过程以及其他参与信号采集的元器件不同,二者的动态范围是有差异的.同时,因为20DX检波器是速度检波器,DSU系列是加速度检波器,所以容易使得人们在判定其由A/D转换器记录位数以及本底噪声定义的瞬时动态范围对数据信噪比的影响时产生混淆.基于模拟数据以及实际试验资料,验证了DSU系列加速度检波器在记录地震数据时,并没有信噪比方面的优势.Coiled geophone and MEMS accelerometer are two major sensors employed in seismic acquisition field practice. The typical examples among the above two are 20 DX（ coiled geophone） and DSUs（ MEMS,Sercel Company）. For 20 DX,the device of performing conversion from analog signal to digital ones is A/D converter,and for DSUs it is ASIC. Due to the different working mechanism of these two sensors,the simultaneous dynamic ranges of 20 DX and DSUs are different. At same time 20 DX is a velocity geophone,and DSUs are accelerometers. Sometimes people are confused how to choose a suitable sensor according to the above complicated factors involved. The author concludes by simulation that the DSUs have no comparative advantage upon 20 DX,where advantage means higher S/N ratio of seismic data.

关 键 词：模拟检波器 数字检波器 记录精度 信噪比 

分 类 号：P631[天文地球—地质矿产勘探]