光钟与氢钟联合的时间尺度算法研究

Combination of an Optical Clock and Hydrogen Masers for Accurate Time Scale Calculation

光钟的频率稳定度和不确定度达到了10-18量级,使其有望成为下一代的时间频率标准,并可能用来重新定义国际单位“秒”.时间尺度作为准确、连续标记时间流逝过程的基准,是高精度时间产生的基础.时间尺度的产生需要依赖连续稳定运行的原子钟,而光钟作为实验室原型设备,一般不能连续运行,因此光钟参与时间尺度计算是个难点问题.提出将Vondrak-Cepek组合滤波算法应用在光钟与氢钟联合计算的时间尺度,以解决间歇运行的光钟参与时间尺度计算的难点问题.首先利用氢钟的时差数据,采用ALGOS算法计算获得连续稳定的氢钟时间尺度.其次利用Vondrak-Cepek组合滤波算法将氢钟时间尺度与光钟的数据综合,获得光钟参与计算的联合时间尺度.最终试验结果证明, Vondrak-Cepek组合滤波算法有效提升光钟与氢钟联合时间尺度的性能,该时间尺度与协调世界时(Coordinated Universal Time, UTC)的时间偏差达到亚纳秒量级.

The frequency stability and uncertainty of the optical clock have reached a magnitude of 10-18,making it a promising candidate for the next generation of time and frequency standards,and it may be used to redefine the international unit“second”.The time scale serves as a benchmark for accurately and continuously marking the passage of time,being the foundation of high-precision time generation.The production of a time scale relies on the continuous and stable operation of atomic clocks;however,optical clocks,as laboratory prototype devices,generally cannot operate continuously,thus involving optical clocks in time scale calculation presents a challenging issue.The proposed application of the Vondrak-Cepek combinedfiltering algorithm for joint time scale calculations with an optical clock and hydrogen masers aims to address the challenges posed by the intermittent operation of an optical clock.Initially,the ALGOS algorithm is used on the time difference data of the hydrogen masers to calculate and obtain a continuous and stable hydrogen maser clock time scale.Subsequently,the Vondrak-Cepek combinedfiltering algorithm is used to integrate the hydrogen maser time scale with the optical clock data to acquire a combined time scale that involves optical clocks in the calculation.Finally,the experimental results prove that the Vondrak-Cepek combinedfiltering algorithm effectively improves the performance of the combined time scale of optical clocks and hydrogen masers,with the time deviation of this time scale reaching the sub-nanosecond magnitude when compared with Coordinated Universal Time.