北斗时频传递链整体绝对校准技术研究

Research on the Integrated Absolute Calibration of BeiDou Time and Frequency Transfer Chain

全球导航卫星系统(GNSS)时频传递因其较好的不确定度水平及使用方便等特点,已成为当前应用最广泛的时频传递技术。时频传递链校准是时间和频率量值精准传递的关键与必要前提,传统的分步绝对校准技术存在校准步骤复杂、不确定度来源多的问题。针对上述问题,该文提出一种整体绝对校准技术,对北斗卫星导航系统(BDS)时频传递链进行整体一次性校准,测量不确定度更低。通过对时频传递链整体绝对校准方法的研究,搭建了时频传递链整体绝对校准系统及实验平台,实现了北斗时频传递链的整体与分步绝对校准实验,评估其不确定度。结果表明两种方法校准结果一致性优于1.76 ns,合成标准不确定度分别评定为0.80 ns与1.00 ns。

Global Navigation Satellite System(GNSS)time and frequency transfer has become the most widely used time and frequency transfer technique due to its fine uncertainty level and ease of use.Time and frequency transfer calibration is the key and necessary prerequisite for the accurate transfer of time and frequency values.The seperated absolute calibration technique suffers from complex calibration steps and multiple sources of uncertainty.To address these problems,an integrated absolute calibration technique with fewer implementation steps and fewer sources of uncertainty is proposed in this paper,i.e.,an integrated one-time calibration of the BeiDou navigation Satellite system(BDS)time and frequency transfer chain,with lower measurement uncertainty.In this paper,through the research on the integrated absolute calibration method of time and frequency transfer chain,the integrated absolute calibration system and experimental platform of the time and frequency transfer chain are constructed,and the seperated absolute calibration and integrated absolute calibration experiments based on one actual BDS time and frequency transfer chain are realized and their uncertainties are evaluated.The results showed that the consistency of the calibration results under the two methods is better than 1.76 ns,and the synthetic standard uncertainties are 0.80 ns and 1.00 ns respectively.