【作者】 栗新伟； 汤亮； 季磊；

【Author】 LI Xin-wei;TANG Liang;JI Lei;School of Electronic and Information Engineering, Soochow University of China;Institute of Acoustics, Chinese Academy of Sciences of China;

【机构】 苏州大学电子信息学院； 中国科学院声学研究所；

【摘要】 铯原子钟的闭环锁定需要一个含有变容二极管的压控振荡器作为微波源,而微波源的精准设计需要准确的变容二极管器件模型,但其数据手册中的参数都是在低频条件下测量得到,无法满足微波源的设计需求。本文利用微带线结构并结合史密斯圆图,研究了射频下变容二极管的C-V特性,在测试数据的基础上进行曲线拟合,完成其在4.595GHz工作频率下模型参数的提取。结电容提取值为7.5p F,与数据手册值7.466p F接近。电路功能正确,满足铯原子钟微波源设计的需要。更多还原

【Abstract】 The closed-loop locking of cesium atomic clocks needs a VCO containing a varactor as the microwave source. In order to design the microwave source accurately, a precise varactor device model is needed. Parameters of varactors in the data sheet are usually measured under the condition of low frequencies, which don’t meet the demand of designing the microwave source. This paper, based on microstrip line structures and combined with the Smith chart, researches the C-V characteristics of a varactor under the condition of radio frequencies. Model parameters of the varactor are extracted at the frequency of 4.595 GHz by means of fitting the curve of the measured data. The tested junction capacitance value is 7.5p F, similar to the given value 7.466 p F. The designed circuit’s function is correct and able to meet the design requirements of the microwave source.更多还原