基于噪声消除的低噪声放大器架构  

Low noise amplifier architecture based on noise cancellation

作　　者：姚若河[1] 许泽韬 YAO Ruohe;XU Zetao(School of Electronic and Information Engineering,South China University of Technology,Guangzhou 510641,China)

机构地区：[1]华南理工大学电子与信息学院,广东广州510641

出　　处：《华中科技大学学报（自然科学版）》2020年第9期82-88,共7页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：广东省科技计划资助项目(2019B010143003)。

摘　　要：提出了一种基于噪声消除与衬底交叉耦合技术的宽带低噪声放大器(LNA)架构,在共栅(CG)与并联反馈组合的噪声消除结构基础上,采用了衬底偏置和衬底交叉耦合技术使输入级的等效跨导增大,提高了噪声消除路径中的消除率,降低了电路的噪声指数.基于噪声消除原理,通过在输入级金属氧化物晶体管(MOS)的衬底上采用无源增益增强的方式,增加了输入级跨导的自由度,改善了原结构输入匹配与噪声指数之间相互制约的问题.根据LNA架构中节点的基尔霍夫电流公式,分析了新架构的增益、输入匹配和噪声指数.与现有噪声消除结构相比,采用衬底交叉耦合技术使这个LNA架构的噪声指数降低了13.3%.A broadband low noise amplifier(LNA)architecture based on noise cancellation and substrate cross-coupling technique was presented.Based on the noise cancellation structure combined with common gate(CG)and shunt feedback,substrate bias and substrate cross-coupling technique was adopted in this LNA architecture to increase the equivalent transconductance of the input stage,the cancellation rate in the noise cancellation path was improved,and the noise figure of the circuit was reduced.Based on the noise cancellation principle,the passive gain-boosting method was adopted on the substrate of the input transistor to increase the input stage transconductance’s degree of freedom,and the mutual restriction between the input matching and noise figure of the original structure was improved.Based on kirchhoff current formula of nodes in LNA architecture,the gain,input matching and noise figure of the new architecture were analyzed.Compared with the existing noise cancellation structure,the LNA architecture reduced the noise figure by 13.3%by using the substrate cross-coupling technique.

关 键 词：低噪声放大器 宽带 噪声消除 交叉耦合 增益增强 

分 类 号：TN722.3[电子电信—电路与系统]