Design and Realization of a Frequency Lock Loop Circuit for a Miniaturized Rubidium Atomic Frequency Standard
SUN Bing-feng1,2,YAN Shi-dong1,WANG Peng-fei1,2, HOU lin-shan1,ZHONG-da1,MEI Gang-hua1
1.Key laboratory of Atomic Frequency Standards, The Chinese Academy of Sciences,Wuhan Institute of Physics and Mathematics, Wuhan, Hubei 430071, China;
2. University of Chinese Academy of Sciences, Beijing 100080, China
Abstract：A frequency-locked loop (FLL) circuit was designed and realized for a miniaturized high performance rubidium atomic frequency standard (RAFS). The 10MHz signal from a VCXO was transformed into the microwave interrogation signal with frequency of 6834.6875MHz by a 45.5645833 multiplier and a consequent 15 one. The 455.645833 multiplier was designed by using the digital phase-locked technique. The frequency modulation of the interrogation signal was realized in the 455.645833MHz signal. The phase noise of the signal was measured and analyzed. Results showed that the fractional stability of the microwave signal is in a level of 3.2×10-12τ-1/2. The short-term frequency stability of a RAFS containing the FLL circuit was tested, and a result of 5×10-12τ-1/2（1 s≤τ≤100 s）was obtained. This result is obviously better than that of an average commercial RAFS.
孙兵锋,阎世栋,王鹏飞,侯林山,钟达,梅刚华. 小型化铷原子频标数字锁频环路设计与实现[J]. 计量学报, 2015, 36(4): 436-440.
SUN Bing-feng,YAN Shi-dong,WANG Peng-fei, HOU lin-shan,ZHONG-da,MEI Gang-hua. Design and Realization of a Frequency Lock Loop Circuit for a Miniaturized Rubidium Atomic Frequency Standard. Acta Metrologica Sinica, 2015, 36(4): 436-440.
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2015, Vol. 36 
