Abstract To focus on the main parameters predictions of high performance rubidium clocks widely used in time keeping systems, a three dimensional state vector estimation model of rubidium clock was presented. The parameters used in this clock estimation model were based on Hadamard variance by nonlinear curve fitting in least-squares sense. With daily data points observed successively for more than 2 months, the state vector estimations of Rubidium clock were obtained. Compared the estimations of the model with the least-squares model, it showed that the characteristic parameters estimation error is much smaller than least-squares linear model, the Model can give the frequency aging rate of rubidium clocks in real time.
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2019, Vol. 40 
