基于ka链路的天基高精度时间传递方法研究

The wide application of high-precision time frequency in space science and basic physical testing requires precision-matched time-frequency transmission technology as a support, while the current transmission technology of time and frequency in space can only achieve 1E-14 frequency transmission accuracy and sub-nanosecond level, which is far from requiring the demand for space-precision time synchronization, and becoming a bottleneck in the application of high precision time frequency in space science and technology. At the same time, with the continuous development of aerospace technology, the human exploration of science extends from the ground to deep space. The number of space stations and space spacecrafts is increasing day by day, and the precision measurement in satellite orbit also need the high precision time and frequency for support, which urgently requires a unified, high-performance space-based timing means to provide high-precision time services for all types of spacecraft to provide protection...This project is aimed at high-precision time transfer technology in space station, and researches the time synchronization method of space based on the Ka link. This project can provide a solution for the high-precision timing requirements of space and ground users and provide certain space science research. Meanwhile, the theoretical support is of far-reaching practical significance for China's ultimate realization of a high-precision integration time scale for the sky.

高精度时间频率在空间科学及基础物理测试等方面的广泛应用需要精度与之匹配的时频传递技术作为支撑，而当前的空间时频传递技术仅能实现1E-14的频率传递精度和亚纳秒量级的时间同步精度，这对于空间高精度时间同步远远无法满足需求，成为高精度时间频率在空间科学技术中应用的瓶颈。同时随着航天技术的不断发展，人类对科学的探索研究从地面延伸至深空，空间站、空间飞行器等各类航天器的数量日益增多，航天器的精密定轨和精密测量等工作也需要更高精度的时间基准作为支撑，这就迫切需要一种统一的、高性能的天基授时手段，以便为各类航天器的高精度时间服务提供保障。. 本项目针对空间站高精度时间传递技术，对基于ka链路的空地时间同步方法进行研究，本项目研究可以为空间及地面用户的高精度授时需求提供一种解决方案，对空间科学研究提供一定的理论支持，对于我国最终实现高精度的天空地一体化时间尺度具有深远的现实意义。

本项目针对空间用户高精度时间传递需求，对基于ka链路时分体制的星地双向时间同步方法和基于载波相位测量的双向时差测量方法进行了深入研究，并对时间同步链路传输中的有关误差进行了详细分析，重点攻克了星地链路中高速运动时延误差的修正方法，并给出了高动态环境下信号跟踪算法。本项目的星地时间传递方法可以支持实现ps级的时间同步精度，比目前北斗星地时间同步精度高出约2个量级，是一种面向空间高精度时间基准向地面和其他空间用户实现高精度授时的解决方案。本项目在4年执行期内按照预定计划完成了各项研究内容和工作目标，并取得了相应成果，共发表论文8篇，授权发明专利3项，授权计算机软件著作权4项，培养博士生1名，硕士生3名，项目成员参加国际国内学术会议3次，按期顺利完成了项目预期成果和目标。