标准时间远程复现系统的不同比对技术对比分析  

Comparative analysis of different techniques of standard time remote reproduction system

作　　者：韩松岳 刘娅[1,2] 王嘉琛 陈瑞琼 许龙霞[1] 李孝辉[1,2] HAN Song yue;LIU Ya;WANG Jia chen;CHEN Rui qiong;XU Long xia;LI Xiao hui(National Time Service Center,Chinese Academy of Sciences,Xi’an 710600,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院国家授时中心,西安710600 [2]中国科学院大学,北京100049

出　　处：《时间频率学报》2022年第4期247-253,共7页Journal of Time and Frequency

基　　金：陕西省自然科学基金资助项目(2018ZDXM-GY-011);国家自然科学基金资助项目(U2031125,11903039);中国科学院“西部之光”人才培养计划“西部青年学者”资助项目(XAB2019B16)。

摘　　要：针对全球卫星导航系统(GNSS)卫星授时难以覆盖10 ns以内的时间服务需求,中国科学院国家授时中心建立了一套低成本,服务范围与GNSS卫星授时相当的标准时间远程复现系统,可以为用户提供优于10 ns的时间服务。作为复现系统的重要组成部分,频率源的选取需要满足精度高、体积小、成本低等需求。铷钟相比于氢钟、铯钟体积小且成本低,相比晶振具有较好的长期稳定性,所以成为复现设备内部频率源的理想选择。通过设计试验,分别在零基线和中基线条件下验证了复现效果,并对比试验了基于共视和全视模式下复现信号的性能差异,试验表明零基线共视条件下复现时间的标准差为0.72 ns,全视条件为0.88 ns,两者性能相当;中基线条件下共视模式所得标准差为1.23 ns,全视条件为3.19 ns,与预期效果存在差异,为此分析了效果差异原因,并给出了系统性能提升的改进方案,为下一步优化系统提供数据支持。In response to the difficulty of GNSS satellite timing to cover time service requirements within 10 ns,the National Time Service Center of the Chinese Academy of Sciences has established a low cost,standard time remote reproduction system with a service range equivalent to GNSS satellite based timing,which can provide users with time services better than 10 ns.As an important part of the reproduction system,the selection of the frequency sources needs to meet the characteristics of high accuracy,small size,and low cost.Compared with hydrogen masers and cesium clocks,rubidium clocks are smaller in size and lower in cost,and have better long term stability than crystal oscillators.They are thus ideal for frequency sources of reproduction equipment.Through the designed experiments,the effect of reproduction was verified under the conditions of zero baseline and mid baseline,and the difference between the reproduced signals based on GNSS common view and GNSS all in view mode were compared and tested.The experiments showed that the zero baseline standard deviation is 0.72 ns under the GNSS common view condition,and amounts to 0.88 ns under the GNSS all in view condition.The performance of the two is equivalent.The standard deviation in the mid baseline case is 1.23 ns under the GNSS common view condition,while it amounts to 3.19 ns under the GNSS all in view condition,which is different from the expectation.For this reason,we analyzed these differences in effect and developed improvement plans for the system to provide data for future optimization.

关 键 词：铷原子钟 时间复现 卫星共视 卫星全视 

分 类 号：P127.1[天文地球—天体测量]