用时钟方波测试地震数采时间精度及系统特性  

Testing of Seismic Digitizer's Time Tag Accuracy and System Characteristic Using Timing Pulses

作　　者：谢剑波[1,2,3] 袁松湧[4,2] 叶世山 杨大克[4,2] 陈建涛[1,3] 丁莉莎 卢子晋[1,3] 劳谦 廖一帆[1,3] 吕仲杭[1,3] XIE Jianbo;YUAN Songyong;YE Shishan;YANG Dake;CHEN Jiantao;DING Lisha;LU Zijin;LAO Qian;LIAO Yifan;LV Zhonghang(Guangdong Earthquake Agency,81 Mid\|Xianlie Road,Guangzhou 510070,China;Institute of Geophysics,CEA,5 South\|Minzudaxue Road,Beijing 100081,China;E-Institute of Earthquake Observation Technology,CEA,5 South-Minzudaxue Road,Beijing 100081,China;Key Laboratory of Earthquake Monitoring and Disaster Mitigation Technology of CEA, 81 Mid-Xianlie Road,Guangzhou 510070,China)

机构地区：[1]广东省地震局,广州市先烈中路81号510070 [2]中国地震局地震观测技术研究院,北京市民族大学南路5号100081 [3]中国地震局地震监测与减灾技术重点实验室,广州市先烈中路81号510070 [4]中国地震局地球物理研究所,北京市民族大学南路5号100081

出　　处：《大地测量与地球动力学》2018年第10期1073-1079,共7页Journal of Geodesy and Geodynamics

基　　金：中国地震局监测运维专项(16A20ZX085)~~

摘　　要：用采集时钟方波信号加以分析的方法评估地震数据采集器的授时、守时服务精度、稳定性及系统特性。将具有时钟误差日志记录的数采的时间精度测试结果与日志记录相比较,二者完全一致;用时钟方波信号实测的数采经验传递函数与用厂家提供的滤波器系数并校正滤波器时间延迟计算的理论频率特性相符。实测结果显示,由于数采守时误差变化呈非线性,即使同一型号的不同数采间,其守时能力也可以差别很大;对于不同的数采及抽取滤波器,由于滤波延迟时间校正的参考点不一致,可导致数采记录数据的时间服务存在1个采样点左右的时间差,这对时间精度要求高的研究工作是不能接受的。This paper introduces a method using recorded timing pulses to estimate the time tag accuracy and system characteristic of a seismic digitizer.The estimated time tag accuracy of a digitizer with internal timing error log is consistent with its error log record.The estimated empirical transfer functions in two other experiments are consistent with their frequency responses calculated from FIR filter coefficients provided by the manufacturer,and their filter delay times are compensated.Our experiment’s results show that the non-linearity of time tag accuracy drift without timing synchronization could differ very much between different digitizers,even using the same model;additionally,that there could be about 1 sample point timing difference among different digitizers and different decimation filters due to the inconsistency in their filter delay time compensation.Such timing inconsistency could be unacceptable in work that requires accurate timing service.

关 键 词：地震数采 时间精度 系统特性 时钟脉冲 

分 类 号：P315[天文地球—地震学]