铯基准钟与守时型原子钟联合守时方法研究

Time-keeping research based on multiple types of atomic clocks is steadly on the move. A cesium atomic fountain clock named NTSC-01has been developed in National Time Service Center under China Academy Sciences(NTSC,CAS), which is promoted to be involved in time-keeping research. the preceding project ”Time-Keeping Combined Cesium Clocks and Hydrogen Masers” has been furtherly developed into the current proposal” Research on Time-Keeping methods based on Cesium Atomic Fountain Clocks and Time-Keeping atomic clocks”, and the project results are ultimately applied in the actual time-keeping work..Cesium atomic fountain clocks with higher accurate and long-term stability is being involved in time-keeping work, which is of positive significance in enhancing performance of national time in our country( UTC(NTSC)). wherefore the running period of cesium atomic fountain clocks are intermittent, which can't meet with the needs of UTC(NTSC), Then it leads to this problem which the previous key methods(atomic time scale algorithies and frequency steering methods )used in time-keeping are not fit to the current situation. Therefore according to the different characteristics of the fountain clocks and time-keeping atomic clocks, the time-keeping methods combining cesium atomic fountain clocks and time-keeping clocks are deeply analysized, meanwhile the experimental system is set up, and the feasibilities of the theoretical methods are verified, and then a whole set of theoretical methods which are fit to time-keeping system combined cesium atomic fountain clocks and time-keeping clocks, finally the accurate and stability of UTC(NTSC) are improved, which is of great significance to ensure the safety of national time in our country.

继续深入开展多种类型原子钟联合的守时方法研究。利用中国科学院国家授时中心研制的铯基准钟NTSC-01，开展铯基准钟参与守时研究，进一步将之前项目组开展的“氢钟和铯钟联合守时方法研究”发展成“铯基准钟与守时型原子钟联合守时方法研究”，并将研究成果应用于实际守时工作中。.具有优良的准确性和长期稳定性的铯基准钟参与守时，对提高我国标准时间UTC(NTSC)的性能具有积极意义。但铯基准钟的运行周期是间歇性的，与标准时间产生和保持的需求不相符（连续的时频信号），导致目前所采用的关键技术（时间尺度算法、频率驾驭算法）不再适用。因此本项目拟根据铯基准钟和守时型原子钟的不同性能特点，深入探讨铯基准钟与守时型原子钟联合的守时方法，搭建实验系统，验证理论的可行性，提出一套适用于铯基准钟与守时型原子钟联合守时的方法，最终实现我国标准时间UTC(NTSC)的综合性能提升，对保障国家用时安全具有重要意义。

时间渗透于人类活动、科学实验和国家建设的各个领域，在社会发展的各个历史时期都受到广泛的重视。国家很多重要的基础设施和行业，例如通信、电信、定位、导航、测绘等，很大程度上依赖于高精度时间服务保障。.铯喷泉钟是复现国际单位制（SI）中时间间隔单位“秒”最准确的装置，其复现的标准秒长几乎没有频率漂移，具有优异的长期稳定性。铯喷泉钟输出信号具有极高的准确性，所以通常将其作为国际原子时（TAI）的校准参考。而守时型原子钟作为守时钟，具有连续稳定运行的特性，氢钟的短期稳定度较铯喷泉钟更优。本项目以铯喷泉钟与守时型原子钟联合守时研究为导向，对铯喷泉钟为参考的时间尺度、基于最优控制理论及融合原子时的频率驾驭方法等方面做了深入研究，搭建实验系统验证方案和理论的可行性，对研究结果进行分析和验证，进而提出一套适用于铯基准钟与守时型原子钟联合守时的理论方法，最终实现标准时间UTC(NTSC)的综合性能提升，对保障国家用时安全具有重要意义，支撑经济社会和国家安全的长远发展。.2018年起，我国时间基准UTC(NTSC)相对于UTC的绝对相位偏差由在±10ns减小至±5ns，稳定度性能得到了整体的提升，综合性能位居世界前四。