摘要
高电子迁移率晶体管（HEMT）的小信号等效电路低温模型是研制致冷低噪声放大器（LNA）与研究晶体管微波特性的基础。该文通过测量HEMT器件在低温环境下直流参数与散射参数（S参数）,构建了包含噪声参量的小信号等效电路,并据此设计了一款覆盖L波段的宽带低温低噪声放大器（LNA）,工作频率12GHz,相对带宽达到66.7%。在常温下放大器功率增益大于28d B,噪声温度小于39K;当环境温度制冷至11K时,噪声温度为1.93.1K,输入输出端口的回波损耗S11和S22均优于-10d B,1d B压缩点输出功率为9.2d Bm,功耗仅为54m W。
The knowledge of the small-signal equivalent circuit cryogenic model of high electron mobility transistors( HEMT) is crucial for the design of cooled low-noise amplifiers( LNA) and is very useful to support the analysis of the transistor microwave performance. This paper describes a method for designing cryogenic L band amplifiers with very low noise for the 1 ~ 2 GHz frequency range,the design is based on measured cryogenic direct current and scattering-parameters combined with a small-signal noise model. At room temperature,the HEMT amplifier achieved a power gain greater than 28 d B and a maximum noise figure of 39 K. When cooled to 11 K,the noise temperature can be reduced to1. 9 ~ 3. 1K,input and output return loss of better than- 10 d B,and 1d B compress point output power 9. 2d Bm with a total power consumption of54 m W.
出处
《微波学报》
CSCD
北大核心
2015年第6期54-58,共5页
Journal of Microwaves
基金
国家自然科学基金(11473060)
关键词
低噪声放大器
低温
高电子迁移率晶体管
小信号模型
噪声温度
low noise amplifier
cryogenic
high electron mobility transistors(HEMT)
small signal modeling
noise temperature
