Abstract：To evaluate reasonably the absolute frequency stability of atomic clocks in the same experimental condition, this paper analyzed the algorithm model and solving process theoretically and studied the method for estimating absolute frequency stability when correlated noises exsisted. It is evaluated by the simulated data of three atomic clocks. Under the assumption of independent noises, the deviation between the test result and theoretical value became larger with the increase of the noise correlation. Considering the noise correlation, the relative error of the test result is always less than 1.7%. The effectiveness of the method was further proved with 360-day real data of four cesium clocks in NIM (National Institute of Metrology) time keeping lab.
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2018, Vol. 39 
