Research On The Key Technology Of Microwave Resource Of Cs Atomic Fountain Frequency Standard

Time and frequency measurement play an important role in national defence and economy development. In order to get rid of the dependence on other countries and establish self-governed time and frequency standard, the research on atomic frequency standard is imperative under the situation.The concept of atomic frequency standard and theory of phase-locked loop are introduced. Both 100MHz and 4GHz phase-locked loop which are used in Cs atomic fountain frequency standard are designed successfully. The problems of amplitude stabilization and phase noise are studied primary. Microwave amplitude stabilized circuit, regenerative divider and regenerative divider and multiplier are manufactured. Experiments prove that: first, the operation of microwave amplitude stabilized circuit is nice and it can be used in other ways; second, extra noise is not introduced by regenerative divider and regenerative divider and multiplier, they are propitious to improve phase noise. Finally, a new scheme is proposed after several schemes of microwave resource are compared. A signal of high stabilization and low phase noise is synthetized by phase-locked loop, mixer, regenerative divider, regenerative divider and multiplier and microwave amplitude stabilized circuit.