Miniaturized Rubidium Frequency Standard Circuit Design,

In the thesis it was studied that the low noise frequency multiplier and the phasemodulation circuit of the rubidium atomic frequency standards(RAFS).The rubidiumatomic frequency standards has been used in so many respects. At the same time,some field put forward request for it, such as the miniaturization of cubage and thesimplification of structure.Firstly, we summarize the history of the development of the atomic frequency standards (AFS), in addition to some basic principles of the rubidium atomic frequency standard. Secondly, the characteristics of the control loop ,the influence of the loop noise on the frequency stability were studied theoretically.In the rubidium atomic frequency standards, the instabilities of the frequency, index and the phase shift of the modulation have strong effects on the stability and accuracy of the output frequency. We realize the indirect frequency modulation through a phase modulation of a 136Hz signal after it is integrated. Through this way we get a FM signal of low noise low distortion and high stability, and we can get the best modulation-depth by adjust the parameters.The frequency multiplier is an important parts for the rubidium atomic frequency standards and its noise is the mostly source of the whole system's noise. The role of the frequency multiplier of the RAFS was analyzed. And we focus on the method and main point during the design stage to get low noise and high performance. The complete circuit and the test result are presented.