Analysis and Design of an Improved Servo System for Rubidium Atomic Frequency Standard

作者：CHEN Yongtai XU Donghui SHEN Yanxin YE Sen TANG Jing SU Lijuan School of Information Engineering Wuhan University of Technology Wuhan Hubei China; Wuhan Institute of Physics; Mathematics Chinese Academy of Sciences Wuhan Hubei China

来源：Wuhan University Journal of Natural Sciences, 2013, 18(01): 67-72.

DOI：10.1007/s11859-013-0895-y

• rubidium atomic frequency standard (RAFS)
• servo loop
• frequency stability
• non-integer voltage controlled crystal oscillator (VCXO)

In this paper, we analyze and design a new type of servo system with noninteger voltage controlled crystal oscillator (VCXO) for rubidium atomic frequency standard (RAFS), which does not require fractional frequency synthesizer. By the establishment of the loop equations with noises and drifts, we prove that all the components of the loop can affect its performance index, and in which, RAFS long-term frequency stability is mainly determined by frequency multiplier, quantum system, and servo amplifier; the short-term one is mostly decided by VCXO. Owing to the elimination of the frequency synthesizer and its additive mixing unit, we can reduce phase noise and stray of the servo system, and it is favorable for miniaturizing the RAFS system. In addition, we adopt some targeted optimization measures to improve the frequency stability index. The good short-term fre-quency stability index is also validated by the test results.

• 出版日期2013-2-24
• 单位武汉理工大学