Abstract
Most composite atomic time scales (TA) are generated by the weighted average algorithm in which the weight of each clock is usually determined by its performance with reference to TA itself. Then, there will be significant correlations between the clocks and the calculated TA in the case of the ensemble composed of a few clocks, which may lead to a large deviation between the estimated and the deserved weight. A new weight algorithm is proposed based on the cooperative covariance matrix of clock differences in the ensemble. The cooperative variance matrix consisting of the instability between any two clocks in the ensemble is given to estimate the performance of each clock using the harmonic average method. The new algorithm was applied to simulated and real data to generate timescales with no human intervention, such as maximum weight setting.
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Data availability
The datasets generated during this study are available from the corresponding author upon request.
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Acknowledgments
This work was supported by the National Natural Science Foundation of China (Grant No. 41931076) and National Key Research and Development Program of China (Grant Number 2020YFB0505801). In addition, the authors would like to thank Professor Bo Wang of Tsinghua University for helpful discussions about hydrogen masers simulation.
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Wang, X., Han, C. & Yang, Y. Timekeeping algorithm based on the cooperative covariance matrix of clock differences. GPS Solut 27, 1 (2023). https://doi.org/10.1007/s10291-022-01334-z
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DOI: https://doi.org/10.1007/s10291-022-01334-z