In order to meet the demand for distributed joint timekeeping system,a remote time comparison system was de-signed,which includes satellite co-visibility,satellite bi-directional,and fiber bi-directional time comparison means.The domestic equipment used in the system has the same time comparison accuracy as imported equipment,achieving high-precision clock differ-ence measurement between laboratories using multiple means.The relative zero value calibration of the time comparison equipment was completed using a mobile calibration station,and a 20-day time comparison was conducted between laboratories that were 50 km apart.The experimental results show that the mean clock difference measured by the three comparison means at the two loca-tions is less than 1 ns,the trend is the same,and the amplitude is similar,and all can accurately measure the clock difference between the two locations.
Time comparisonMobile calibration stationZero calibration
NETL
NSTL
万方数据
