Abstract：Atomic clock difference prediction is the key step in atomic clock time scale generation and atomic clock control. The atomic clock is a precise signal source, and its signal consists of the determined signal part which is corrected by the prediction algorithm and the inherent noise, which is a random part. The hydrogen and cesium clock mainly contain two kinds of noise, that is, white frequency noise and random walk frequency noise. These two kinds of noise are the main factors that produce the uncertainty of prediction. The mathematical expression of the prediction uncertainty of the time difference data of the atomic clock is derived, based on the mathematical model of the atomic clock, and the minimum prediction uncertainty of the clock group is obtained. The influence of the number of clocks in the clock group on the prediction uncertainty is analyzed. Finally, the correctness of the theory is verified.
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2019, Vol. 40 
