摘要
卫星双向时间频率传递(TWSTFT)是协调世界时(UTC)产生过程中的重要时间比对技术手段,其精度可达0.5ns。目前,全球大约有20多个时间保持水平最高的守时实验室利用卫星时间和测距设备(SATRE)进行连续的实验室间远距离卫星双向时间比对工作。然而SATRETWSTFT的性能主要受到了周日效应的影响,其在某些链路上变化幅度甚至可达2ns。2016年2月,国际权度局(BIPM)和国际时频咨询委员会(CCTF)卫星双向工作组(WGTWSTFT)共同发起了基于软件接收机(SDR)的国际卫星双向时间比对试验研究,并取得了较为满意的结果。对该研究小组的工作进行了简单的回顾,主要以SATRETWSTFT和GPSPPP或IPPP技术为参考对SDRTWSTFT进行了分析评估,结果表明:SDRTWSTFT在洲际内的多数链路上对SATRETWSTFT的周日效应的平均增益因子为2~3,而在洲际间的长基线链路上改善了30%~40%。从2017年10月开始,SDR卫星双向成为了UTC时间比对链路的备份链路,预计未来几年将成为UTC时间比对的正式链路。
Two-way satellite time and frequency transfer (TWSTFT or TW for short) is a primary technique with precision of 0.5 ns for the generation of coordinated universal time (UTC). About 20 leading time laboratories around the world carry out continuously TWSTFT via Satellite and SATRE. One of the major uncertainty sources is the diurnal in the SATRE TWSTFT measurements. The observed peak-to-peak variations can be up to 2 ns in some cases. In 2016, the BIPM and the Consultative Committee for Time and Frequency (CCTF) working group (WG) on TWSTFT launched a pilot study on the application of SDR receivers in the UTC TWSTFT network. The results are satisfying. In this paper the SDR TWSTFT works are briefly reviewed and the results are compared with SATRE TWSTFT and GPS PPP or IPPP. It is indicated that within one continent the SDR TWSTFT link demonstrates a significant gain factor of 2-3 in reducing the diurnals and the continental STARE TWSTFT has been improved 30%-40% for the diurnals. The SDR TWSTFT became the backup UTC time transfer link since 2017 October and it is expected to be used formally for the generation of UTC in next several years.
作者
江志恒
武文俊
JIANG Zhi-heng;WU Wen-jun(Bureau International des Poids et Measures (BIPM), Paris F92312, France;National Time Service Center, Chinese Academy of Sciences, Xi’an 710600, China;Key Laboratory of Time and Frequency Primary Standards, Chinese Academy of Sciences, Xi’an 710600, China;School of Astronomy and Space Science, University of Chinese Academy of Sciences, Beijing 101048, China)
出处
《时间频率学报》
CSCD
2019年第3期196-205,共10页
Journal of Time and Frequency
基金
国家自然科学基金资助项目(11703030)
中国科学院“西部之光”人才培养计划西部青年学者基金资助项目(XAB2017A06)
关键词
协调世界时
软件接收机
卫星双向时间频率传递
周日效应
不确定度
coordinated universal time (UTC)
software-defined receiver (SDR)
two-way satellite time and frequency transfer (TWSTFT)
diurnal
uncertainty
