Abstract: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.
XIE Jianbo,YUAN Songyong,YE Shishan et al. Testing of Seismic Digitizer’s Time Tag Accuracy and System Characteristic Using Timing Pulses[J]. jgg, 2018, 38(10): 1073-1079.