Non-reciprocity correction using broadcast ephemeris in Two-way Satellite Time and Frequency Transfer （TWSTFT）
作者单位：School of Electronic Science and EngineeringNational University of Defense Technology
会议名称：《第四届中国卫星导航学术年会》
会议日期：2013年
学科分类：08[工学] 080401[工学-精密仪器及机械] 081105[工学-导航、制导与控制] 0804[工学-仪器科学与技术] 0825[工学-航空宇航科学与技术] 0811[工学-控制科学与工程]
关 键 词：TWSTFT non-reciprocity corrections Sagnac correction signal path geometry correction broadcast ephemeris
摘 要：Two-way satellite time and frequency transfer （TWSTFT） is applied in BeiDou Navigation Satellite System for time synchronization of the ground stations. In fact, the geostationary （GEO） satellites have periodic motions around their planned orbits instead of being stationary to the ground stations, which results in periodic fluctuations of Sagnac correction and signal path geometry correction in TWSTFT. Precise TWSTFT is relaying on the non-reciprocity corrections. An analysis method with broadcast ephemeris of GEO satellite for Sagnac correction and signal path geometry correction is introduced in this paper. With this method, TWSTFT experiment result using BeiDou GEO satellite at 140°E of three links between Beijing and three different sites is analyzed and the periodic fluctuation of Sagnac correction and signal path geometry correction are presented in detail. The fluctuation range of Sagnac correction is from 0.04ns to 0.16ns and that of signal path geometry correction is from 0.01ns to 0.53ns for the three links, which shows that Sagnac correction and signal path geometry correction can not be ignored in time transfer requiring sub-nanosecond precision generally for the three links.