An Optimized Weighting Method for Atomic Clock Ensemble
YU Hang1,2,ZHANG Lei1,SONG Wen-xia2,WANG Yu-zhuo2
1. Department of Artificial Intelligence and Data Science, Hebei University of Technology, Tianjin 300130, China
2. National Institute of Metrology, Beijing 100029, China
Abstract Atomic clock group integration technology is widely used in time keeping systems to maintain the accuracy, stability and continuity of time scale. However, there is always a certain correlation between atomic clocks in the same laboratory, which limits the performance of atomic time scales. Based on the correlation between the atomic clock ensemble and its covariance matrix, this paper investigates the influence of same environmental factors on the frequency characteristics of atomic clock. A new weighting method for atomic clock ensemble is designed with optimization theory. It was applied to the cesium clock ensemble at NIM. The results showed the new method could reduce greatly the frequency instability of the clock ensemble.
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2022, Vol. 43 
