高稳定度低温蓝宝石微波频率源设计  

Design of Cryogenic Sapphire Oscillator with High Frequency Stability

作　　者：朱玺 陈海波 黄凯 高连山 王亮 ZHU Xi;CHEN Hai-bo;HUANG Kai;GAO Lian-shan;WANG Liang(Beijing Institute of Radio Metrology and Measurement,Beijing 100039,China)

机构地区：[1]北京无线电计量测试研究所,北京100039

出　　处：《宇航计测技术》2020年第1期12-16,共5页Journal of Astronautic Metrology and Measurement

摘　　要：利用蓝宝石晶体在低温下具有低损耗的特点,设计并研制了本征模式为WGH12,0,0的蓝宝石微波腔。当温度稳定在6.4K时,其Q值能够达到4.0×10^8。以此微波腔为基础,形成正反馈振荡回路,并根据POUND电路原理对环路中振荡信号的相位进行控制,提高整机稳定度指标。为满足频率互比测试的需求,采用共用一个低温装置的方案,构建了两台低温蓝宝石微波源,一路输出频率为9.204GHz,另一路输出频率为9.205GHz,两路信号混频,并用时间间隔计数器测量差频信号的频率。经计算,低温蓝宝石微波频率源的秒级频率稳定度达到了3.28×10^-15。Cryogenic sapphire crystal has a characteristic of low loss.Based on this property,sapphire loaded cavity operating on the whispering-gallery mode WGH12,0,0 has been constructed.The Qfactor can achieve 4.0×10^8 when the cavity temperature is controlled at 6.4 K.Then on this basis,positive feedback loop oscillator is implemented.In order to improve the frequency stability,the phase of oscillator is controlled according to POUND circuitry.While to test the relative frequency stability,two cryogenic sapphire oscillators are set in one cryocooler cryostat.The two CSOs oscillate at 9.204 GHz and 9.205 GHz,respectively.After mixing and calculating,the relative frequency stability of 3.28×10^-15/s is obtained.

关 键 词：低温蓝宝石 微波频率源 Q值 频率稳定度 

分 类 号：TH714[机械工程—测试计量技术及仪器]