Design Of Time In-phase Systerm Of Broad Band Seismic Recorder Based On GPS

Time service is a important content in seismic observation. measure precision of Time-synchronization effects the quality of recording.This is most valuable data in seismic data analyze and seismic wave conversion。Nowadays seismology observation has high require about time service ,GPS time service system is used in seismic observation station inside and outside of the country . GPS is a planet wireless conductance system which is global and all-weather,GPS can offer high precision time orientation information to infinite user,Clock precision reachs 10?6 magnitude。not only changes traditional time method of quartz crystal clock ,But also replaces wireless shortwave and even more lowfrequency signal and TV signal whose overlay range is limited and low precision,Offers advantage to geology field task , achieve automatization and high precision of seismic flow observation . This paper gives a time-synchronization technique bases on GPS time service signal which is used in broad band seismic recorder。By world coordination time offered by GPS--UTC(USNO),adjust local clock base on GPS signal ,Gain high nicety clock signal , clock precision reachs 10-6。This clock is the time source of broad band seismic recorder, bring the whole seismic recorder works in same time base.1PPS time base with high stability can be used as in-phase, spring, time and start-stop of every collection mode, While the scale under second make a precise time mark to receive data of broad band seismic recorder.This paper analyses crystal oscillator's character and technique targets, and the changes of these technique targets effect the time of crystal oscillatorGives the error mode of crystal oscillator time, by discussing GPS system and time service theory, we analyze random character of GPS second pulse error. we combine long-time stability of receiver's output signal and short-term stability...