Research

Timekeeping system is the foundation of modern society. Distributed timekeeping has unique advantages in making full use of atomic clock resources and improving the stability and reliability of timekeeping system. At the same time, the contradiction between “distributed clock ensemble framework” and “real-time performance” is a major challenge. Thanks to the fiber-based frequency synchronization technique, atomic clock signal can be recovered with high fidelity at remote site. Using this technique, a frequency synchronization network in Beijing has been constructed, and atomic clocks of different institutions can be compared and measured with those of Tsinghua University in real time. Based on the network, a series of investigations have been carried out, including the generation of real-time free-running time scale with remote clocks on the network, correlation measurement of co-located hydrogen masers, the study on the real-time performance enhancement of free-running time scale as well as the study of the influence of correlation on the time scale generation. In the near future, a unified timing network with the advantages of real-timing, high reliability and flexibility will be realized.