Research on smart clock synchronization method based on GPS for seismic data acquisition and recording system

Abstract

When a large-scale seismic data acquisition and recording system is applied for long-term continuous data acquisition, it is often affected by factors such as temperature, excitation level and acceleration changes perceived by the crystal unit. Since there is no accumulative error for GPS time and the short-term stability of GPS local clock is outstanding, this paper designs a scheme that uses GPS clock as standard clock to time FCU(Field Control Unit), then uses GPS highprecision second pulse, and uses least square method and bisection method to calibrate local clock frequency. The test results show that the clock synchronization error of this scheme is less than 800ns, which has the advantages of low cost and good reliability, and can meet the needs of clock synchronization for long-time continuous data acquisition of largescale seismic acquisition and recording system.