关于氢原子钟的钟差预报研究

Research on clock difference prediction of hydrogen maser

原子钟钟差预报对于守时系统稳定运转有着重要的意义,其可为系统实时时间尺度计算提供基础,为原子钟异常值检测提供参考。氢原子钟短期稳定性较好,常作为系统主钟参与原子钟比对,开展氢原子钟钟差预报研究。为更合理有效的实现氢原子钟钟差预报,提出针对氢原子钟不同频率漂移情况选择不同预报模型方法,随后开展钟差预报组合模型研究,给出常规加权组合模型,运用条件极值法推导出极值权组合模型,同时提出等权组合模型,对比分析各自组合特点、预报结果,给出预报组合模型建议,最后计算时间尺度并与传统方法进行对比,结果表明依据本文钟差预报方法计算得到的时间尺度稳定度在平均时间为64 h的稳定度达4.96×10-15,128 h的稳定度达2.36×10-15,较传统方法计算得到的时间尺度长期稳定度提升。

The clock difference prediction of atomic clock is of great significance to the stable operation of the time keeping system. It can provide a basis for the real-time time scale calculation of the system and a reference for the detection of abnormal values of the atomic clock. Hydrogen atomic clock has good short-term stability, which is often used as the master clock of the system to participate in atomic clock comparison. This article conducts the research on the clock difference prediction of the hydrogen maser. In order to achieve the clock difference prediction of the hydrogen maser more reasonably and effectively, this article proposes a method of selecting different prediction models aiming at different frequency drift conditions of the hydrogen maser. Then, the researches on the combination models of clock difference prediction are conducted, the conventional weighted combination model is given, the conditional extremum method is used to derive the extreme weight combination model, and an equal weight combination model is proposed. The characteristics and prediction results of different combination models are compared and analyzed, and the proposal of the combination model is given. Finally, the time scale is calculated and compared with that of the traditional method, the results show that using the proposed clock difference prediction method, the calculated time scale stability is 4.96×10-15 in the average time of 64 h, and the calculated time scale stability is 2.36×10-15 in the average time of 128 h, which is better than the long-term stability of the time scale calculated using the traditional method.