Abstract：To reduce the noise in the clock frequency, since the hydrogen atomic clock frequency differences are non-linear and non-stationary with time, the denoise algorithm based on ensemble empirical mode decomposition is put forward. Firstly, the clock frequency differences are added a certain intensity noise; then decompose the differences with the EMD algorithm, repeat this step many times; finally, calculate the mean of the same components to get the denoise clock frequency differences. Compared with the wavelet algorithm in the time domain and frequency domain, the result shows that, the algorithm put forward in this paper is better than the wavelet algorithm in the denoise of the clock frequency differences, the data variance is 0.7263% which is 2.707% in the wavelet algorithm, the data become more stable.
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2017, Vol. 38 
