The Low Noise Frequency Synthesizer Used In The Cesium Atomic Fountain Clock And The Physical Part Of The CPT Maser

The freqency synthesizer used in the cesium atomic fountain clock and the microwave cavity designed for the CPT Maser is discussed in this paper.cThe cesium atomic fountain clock is the time and frequency standards. And the quality of the freqency synthesizer impacts the performance of the atomic fountain clock. The methods and facture of frequency synthesizer used for cesium atomic fountain clock is explained in this article. The digital phase locked loop is used.And the ouput frequency signal is 9.2 GHz in this design. It obtains the phase noise of -82 dB[Rad~2/Hz]@1Hz.The Institution Electronics National(INRIM) in Italy and National Institute of Standards and Technology(NIST) in USA have carried out experiment in frequency standard based on the coherent population trapping. Based on the advantages of CPT and the progress in frequency standards, CPT maser vapor cell frequency standard will be a candidate for satellite space-positioning systems-Galileo. In this paper we will discuss the design and test of physical and electronic systems in CPT maser focusing on the design and parameters of microwave cavity.