Precision analysis of non-continuous two-way satellite time comparison

Abstract

As one of the high accuracy time comparison methods, Two-way Satellite Time and Frequency Transfer (TWSTFT) is one of the important methods for Bureau International des Poids et Mesures (BIPM) to organize international comparison, calculation of the International Atomic Time (TAI) and Coordinated Universal Time (UTC). Due to the interference of emitting device of TWSTFT to co-located devices of Very Long Baseline Interferometry (VLBI) or International GNSS Service (IGS) and the limitation of satellite transponder resources, the comparison is not proceed continuously. Ten consecutive days of data from C-band TWSTFT Network of National Time Service Center (NTSC) was used for analyzing the precision of non-continuous TWSTFT. The raw data of non-continuous TWSTFT was dealt with linear interpolation method. Then the result was compared with continuous TWSTFT which was seen as the true value. Finally, the influence of interval to the precision of non-continuous TWSTFT was analyzed. The comparison shows that: when the interval time is less than 2.5 days, the RMS of the difference between non-continuous and continuous TWSTFT is better than 1 ns; when the interval time is 0.5 day, the RMS is better than 0.5 ns.