DVB-C系统中射频宽带低噪声放大器电路的设计研究  

Study of Designing Wide Band LNA for DVB-C System

作　　者：魏明[1] 黄成[1] 吴建辉[1] 

机构地区：[1]东南大学国家专用集成电路系统工程技术研究中心,南京210096

出　　处：《电子器件》2007年第3期894-896,共3页Chinese Journal of Electron Devices

摘　　要：本文根据DVB系统对LNA的特殊要求,阐述了负反馈展宽放大器频带的原理,讨论了通过设计并联负反馈的手段来实现LNA宽频带稳定性,并在此基础上,设计出一种宽带LNA的拓补结构,并采用将负反馈解析计算与仿真优化相结合的LNA设计方法,给出了LNA最终设计的仿真及实测结果.实验结果和设计结果吻合较好.该LNA带宽为50MHz～900MHz,功率增益10.4dB,带内增益波动0.6dB,带内噪声系数2.7dB～3.5dB.Based on the special requirements of DVB-C system to LNA, the negative feedback principle of extending an amplifier＇s frequency band was presented. The method of implementing LNA stability in broad frequency by designing the parallel negative feedback network was discussed. A new topology structure of wide band low noise amplifier was designed. Also, a method of combining negative feedback analytic calculation and optimization simulation was presented here with the final simulation and test results. The measured results fit with the design results well. The LNA circuit has achieved an operating frequency ranging from 50 MHz to 900 MHz , a power gain between 10. 1 dB and 10. 7 dB, a noise figure from 2. 7 dB to 3. 5 dB.

关 键 词：LNA 负反馈 噪声系数 VSWR 

分 类 号：TN722.1[电子电信—电路与系统]