时间频率量值源头的独立自主是建设我国综合PNT体系的重要基础.为进一步评估基于我国国家秒长基准的原子时标守时能力,利用改进的有限脉冲响应钟差预测与频率调控方法,对激光冷却铯原子喷泉钟与氢钟的频差实测数据进行后处理,分别产生了自主型时标和溯源型时标.通过国际原子时合作链路将两个时标与协调世界时进行了长期比对实验,结果表明:2021年12月~2022年12月期间,两个时标的时间偏差均优于±4 ns、频率稳定度均优于8×10-16/5 d.
Timekeeping capability analysis of steering hydrogen maser to NIM5
The independence of time and frequency standards is an important basis for the comprehensive PNT system construction in China.To further evaluate the timekeeping capability of the atomic time scale based on the national primary frequency standard,the improved FIR clock difference prediction and frequency control method is used to post-process the frequency difference of the cesium atomic fountain clock relative to the hydrogen maser.By post-processing,the autonomous time scale and traceable time scale are generated respectively.The two-time scales are compared with UTC by the international atomic cooperation link.The long-term experimental results show that both of the time differences between the two-time scales and UTC are less than±4 ns and the frequency stability is less than 8×10-16/5 d from December 2021 to December 2022.
cesium atomic fountain clocknational primary frequency standardatomic time scaleatomic clocksteering algorithm