Atomic clock frequency jumps directly influence the accuracy and reliability of timekeeping systems. The necessary corrections are typically implemented by postprocessing mutual comparison data between multiple atomic clocks based on the overly strict assumption that these atomic clocks are independent of each other. This paper describes the concept of a mirror clock, which enables atomic clock frequency jumps to be identified in real time without any assumptions. By comparing whether the real measured data and a corresponding mirror clock prediction fall within a confidence interval determined by the uncertainty of past physical clock data, atomic clock frequency jumps can be effectively identified and corrected. The results of several experiments using three hydrogen masers verify that the precision and recall of simultaneous jump identification reach 96.41% and 73.49%, respectively.

The atomic clock prediction algorithm is a critical part of the atomic time scale system to ensure its stability and accuracy. Random pursuit strategy (RPS) has been verified on the prediction capability of hydrogen maser and cesium clock in our previous works. This method is applied to deal with data impacted by different noise types including hetero-variance white noises and jumps. Nevertheless, it is difficult to apply RPS to real-time clock prediction, owing to its computational complexity. To alleviate it, we further improved our original algorithm by simplifying the random grouping using a pseudo-random strategy. In our work, theoretical analysis and necessary simulations of the pseudo-random pursuit strategy (PRPS) are presented, and the experimental results show PRPS's remarkable advantage in terms of operational efficiency. Compared to the original algorithm, it shows comparable accuracy and stability for prediction. PRPS takes only 1/p fitting time consumption as long as RPS starts from the second prediction. PRPS is faster, more efficient, and easier to employ when utilizing a clock predictor as the output of a system than RPS.INDEX TERMS Atomic clock, pseudo random, real-time prediction, anomalous behaviors, uncertainty, time complexity.