Research On Correlative Technology Of Rubidium Atomic Clock By Micro Laser Pumping

Among the traditional microwave atomic frequency standards,rubidium atomic frequency standard is the most widely used frequency standard.Its development direction is to pursue lower power consumption,smaller volume and higher stability.The existing commercial rubidium clocks still have some shortcomings,such as high power consumption and large volume.Therefore,in order to reduce power consumption and volume,the light source and radio frequency chain of rubidium atomic frequency standard are studied in this paper.For the light source part,the advantages of using laser instead of spectral lamp as pumping light source are introduced.A control circuit for rubidium atomic pumping based on vertical cavity surface emitting laser(VCSEL)is developed,which includes the development of constant current source,temperature control circuit and feedback control of laser frequency.The current fluctuation and temperature control accuracy meet the design requirements.The laser frequency is locked on the D1 line of rubidium atom.Compared with using spectral lamp as pumping light source,the scheme is optimized in volume and power consumption.For the part of radio frequency chain,this paper introduces a scheme of using phase-locked loop to generate phase discontinuous and modulated microwave signal.The single chip computer is used to control the timing reasonably,effectively shield the noise introduced by the frequency of modulation signal when jumping.In addition,temperature compensation is taken for microwave power.The closed-loop stability of the whole machine is measured to be about 1.2×10-10-11/(?)(1s???100s).This index has not deteriorated compared with the original scheme,and meets the requirements of small commercial rubidium clock.In addition,the power consumption of this scheme is only half of that of the original scheme,and the power of the microwave signal generated can be adjusted in a wide range with high precision.The improved scheme proposed in this paper can effectively reduce the complexity of the structure,reduce the volume,and reduce the power consumption,which provides a basis for the integration and miniaturization development of rubidium clock.