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arXiv · 1906.02459

Real-time free-running time scale with remote clocks on fiber-based frequency network

Y. C. Guo·B. Wang·F. M. Wang·F. F. Shi·A. M. Zhang·X. Zhu·J. Yang·K. M. Feng·C. H. Han·T. C. Li·L. J. Wang
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Abstract

In this paper, we propose a real-time free-running time scale based on four remote hydrogen masers. The clocks in the ensemble were scattered around Beijing, connected by urban fiber links using a novel frequency synchronization system. The remote clock ensemble prevents the time scale from potential problems caused by correlation among co-located clocks. Insofar as it is real-time, it fulfills the requirements for applications such as navigation, telecommunications and so on. The free-running time scale is updated every 1200 s, and a disturbance-resistant algorithm makes it robust to fiber link disturbances and clock malfunctions. The results of a continuous experiment over 224 days are reported. The stability of the time scale outperformed any clock in the ensemble for averaging times of more than approximately 10000 s.

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Y. C. Guo, B. Wang, F. M. Wang, F. F. Shi, A. M. Zhang, X. Zhu, J. Yang, K. M. Feng, C. H. Han, T. C. Li, L. J. Wang. 2019-06-06. Real-time free-running time scale with remote clocks on fiber-based frequency network. https://doi.org/10.1088/1681-7575/ab299d

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