An overview on GNSS carrier-phase time transfer research  

作　　者：ZHANG Ming Lü JinHu BAI ZhengDong JIANG ZhiQi CHEN BoBo 

机构地区：[1]The Key Laboratory of Systems and Control,Institute o f Systems Science,Academy of Mathematics and Systems Science,Chinese Academy of Sciences,Beijing 100190,China [2]School of Automation Science and Electrical Engineering,Beihang University,Beijing 100191,China [3]Institute of Geomatics of Tsinghua University,Beijing 100084,China [4]Management and Department of Energy and Resources Engineering,College of Engineering,Peking University,Beijing 100871,China

出　　处：《Science China(Technological Sciences)》2020年第4期589-596,共8页中国科学（技术科学英文版）

基　　金：supported in part by the National Key Research and Development Program of China(Grant No.2016YFB0800401);in part by the National Natural Science Foundation of China(Grants Nos.61621003,61532020&11472290)。

摘　　要：Global navigation satellite system(GNSS)carrier phase observations are two orders of higher accuracy than pseudo-range observations,and they are less affected by multipath besides.As a result,the time transfer accuracy can reach 0.1 ns,and the frequency transfer stability can reach 1×10^-15 with carrier phase(CP)method,therefore CP method is considered the most accurate and promising time transfer technology.The focus of this paper is to present a comprehensive summary of CP method,with specific attention directed toward day-boundary clock jump,ambiguity resolution(AR),multi-system time transfer and real-time time transfer.Day-boundary clock jump is essentially caused by pseudo-range noise.Several approaches were proposed to solve the problem,such as continuously processing strategy,sliding batch and bidirectional filtering methods which were compared in this study.Additionally,researches on AR in CP method were introduced.Many scholars attempted to fix the single-difference ambiguities to improve the time transfer result,however,owing to the uncalibrated phase delay(UPD)was not considered,the current studies on AR in CP method were still immature.Moreover,because four GNSS systems could be used for time-transfer currently,which was helpful to increase the accuracy and reliability,the researches on multi-system time transfer were reviewed.What’s more,real-time time transfer attracted more attention nowadays,the preliminary research results were presented.Global navigation satellite system（GNSS） carrier phase observations are two orders of higher accuracy than pseudo-range observations, and they are less affected by multipath besides. As a result, the time transfer accuracy can reach 0.1 ns, and the frequency transfer stability can reach 1×10-15 with carrier phase（CP） method, therefore CP method is considered the most accurate and promising time transfer technology. The focus of this paper is to present a comprehensive summary of CP method,with specific attention directed toward day-boundary clock jump, ambiguity resolution（AR）, multi-system time transfer and real-time time transfer. Day-boundary clock jump is essentially caused by pseudo-range noise. Several approaches were proposed to solve the problem, such as continuously processing strategy, sliding batch and bidirectional filtering methods which were compared in this study. Additionally, researches on AR in CP method were introduced. Many scholars attempted to fix the single-difference ambiguities to improve the time transfer result, however, owing to the uncalibrated phase delay（UPD） was not considered, the current studies on AR in CP method were still immature. Moreover, because four GNSS systems could be used for time-transfer currently, which was helpful to increase the accuracy and reliability, the researches on multi-system time transfer were reviewed. What’s more, real-time time transfer attracted more attention nowadays, the preliminary research results were presented.

关 键 词：carrier phase(CP) TIME TRANSFER day-boundary clock jump AMBIGUITY resolution(AR) MULTI-SYSTEM TIME TRANSFER real-time TIME TRANSFER 

分 类 号：TN967.1[电子电信—信号与信息处理]