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arXiv · 1705.06580

The correlation of co-located hydrogen masers

Y. C. Guo·B. Wang·H. W. Si·Z. W. Cai·A. M. Zhang·X. Zhu·J. Yang·C. H. Han·T. C. Li·L. J. Wang
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Abstract

The correlation of co-located hydrogen masers (H-masers) is difficult to measure because their common-mode noise induced by the environment will be cancelled out during the comparison measurement. With the development of fibre-based high-precision time and frequency transfer technique, the correlation of co-located hydrogen masers can be directly measured with the help of remote H-masers. Recently, a fiber-based frequency synchronization network was constructed in the Beijing region by connecting 5 H-masers from 4 institutions. The correlation coefficient of atomic clocks is defined and the correlation between two co-located H-masers is measured using both experimental and simulative methods. The results show that the correlation is not prominent until the averaging time is larger than $\sim10^3$s; then, the coefficient grows rapidly for averaging times ranging from $\sim10^3$s to $\sim10^5$s and decreases beyond $\sim10^5$s up to 5 days.

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Y. C. Guo, B. Wang, H. W. Si, Z. W. Cai, A. M. Zhang, X. Zhu, J. Yang, C. H. Han, T. C. Li, L. J. Wang. 2017-05-15. The correlation of co-located hydrogen masers. https://arxiv.org/abs/1705.06580

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