基于软件接收机技术的卫星双向时间传递性能分析  

Analysis of the performance of SDR TWSTFT

作　　者：张虹[1,2] 董绍武[1,2] 袁海波[1,2] 武文俊[1,2] ZHANG Hong;DONG Shao-wu;YUAN Hai-bo;WU Wen-jun(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)

机构地区：[1]中国科学院国家授时中心,西安710600 [2]中国科学院时间频率基准重点实验室,西安710600

出　　处：《时间频率学报》2019年第4期284-291,共8页Journal of Time and Frequency

摘　　要：卫星双向时间传递(TWSTFT)是目前UTC实现的主要技术手段,可以实现的比对精度为0.2~0.3 ns。它的主要不确定度源是日变化(周日效应),周日效应在极端情况下峰峰值可以达到2 ns。为了减少周日效应的影响,开始了将SDR接收机应用于TWSTFT的前沿研究。通过分析比较基于SDR技术卫星双向时间比对和传统卫星双向时间比对两种时间比对技术的工作原理和比对结果,验证基于SDR技术的双向时间比对的性能,为SDR双向时间比对链路将来成为UTC/TAI计算提供参考。初步结果表明:基于SDR技术的卫星双向时间比对的性能较传统双向比对有一定的提高,尤其是短基线时间传递比较明显,时间不确定度(10 ks内)达到0.1 ns,较传统双向链路提高了44.9%。Two way satellite time and frequency transfer(TWSTFT) is a primary technique for UTC realization at present, and its time transfer accuracy is up to 0.2 to 0.3 ns. The dominant source of its uncertainty is the daily variations(diurnals), whose peak-to-peak amplitude could be up to 2 ns in extreme cases. In order to reduce the impact of the diurnals, a pilot study of the application of SDR receivers in TWSTFT was done. To study the performance of SDR TWSTFT, the difference of the principle and the time transfer result between SDR TWSTFT and traditional TWSTFT is analyzed. Our research work aims to provide a reference for using the SDR TWSTFT as the UTC/TAI link in the future. In our research, the SDR TWSTFT shows a performance that is better than that of the traditional TWSTFT. In the short-baseline case the SDR shows an obvious improvement. The time variance of SDR TWSTFT(within 10 000 seconds) has been reduced to 0.1 ns, which is 44.9% better than the traditional TWSTFT.

关 键 词：软件接收机技术 卫星双向时间比对 时间不确定度 

分 类 号：P127.1[天文地球—天体测量]