PAGEII低噪声放大器设计仿真及优化摘要快速发展的无线通信对微波射频电路如低噪声放大器提出更高的性能。低噪声放大器(LNA)广泛应用于微波接收系统中，是重要器件之一，它作为射频接收机前端的主要部分，其主要作用是放大天线从空中接收到的微弱信号，降低噪声干扰，以供系统解调出所需的信息数据。它的噪声性能直接决定着整机的性能，进而决定接收机的灵敏度和动态工作范围。而近年来由于无线通信的迅猛发展也对其提出了新的要求，主要为：低噪声、低功耗、低成本、高性能和高集成度。所以本论文针对这一需求，完成了一个2.45GHz无线射频前端接收电路的低功耗低噪声放大器的设计。本文从偏置电路、噪声优化、线性增益及输入阻抗匹配等角度分析了电路的设计方法，借助ADS仿真软件的强大功能对晶体管进行建模仿真，在这个基础上对晶体管的稳定性进行了分析，结合Smith圆图，对输入输出阻抗匹配电路进行了仿真优化设计，设计了一个中心频率为2.45GHz、带宽为100MHz、输入输出驻波比小于1.5、噪声系数小于2dB和增益大于15dB的低噪声放大器。关键词：微波；低噪声放大器；噪声系数；匹配电路；ADS仿真ABSTRACTRapidgrowthofwirelessdatacommunicationshasincreasedthedemandforhighperformanceRF&Microwavecircuits,SuchasMicrowaveLowNoiseAmplifiers.TheLNAisoneofthemostimportantandbroadcomponentsinMicrowavecommunicationsystemreceiver,asthemainpartoftheRFfront-endreceiver,thefunctionofthelownoiseamplifierisamplifyingthefaintsignalwhichinceptedfromairbytheantenna.Itcanreducethenoisejamming,soastodemodulaterightinformationforthesystem.ThenoiseperformanceoftheLNAwillaffecttheperformanceofthewholesystemdirectly,andthendecidingthesensitivityanddynamicworkingscopeofthereceiver.Fromtheaspectofbiascircuit,noiseoptimization,lineargain,impedancematch,andthedesignmethodologyforLNAisanalyzed,ThisarticlecarriesonthemodellingsimulationwiththeaidoftheADSsimulationsoftware'spowerfulfunctiontothetransistor,hascarriedontheanalysisinthisfoundationtotransistor'sstability,hasusedtheSmithcirclediagram,toinputtheoutputimpedancematchcircuittocarryonthesimulationoptimizationdesign.aradiofrequencypoweramplifierisdesigned,whichhasacentrefrequency2.45GHz,bandwidth100MHz,I/OVSWRlessthan1.5,Noisecoefficientlessthan2dBandWattandgain15dB.KeyWords：microwave;low-noiseamplifier;noisefigure;matchingcircuit;ADSsimulation目录TOC\o"1-3"\h\z\uHYPERLINK\l"_Toc327113494"1引言PAGEREF_Toc327113494\h1HYPERLINK\l"_Toc327113495"1.1课题研究背景PAGEREF_Toc327113495\h1HYPERLINK\l"_Toc327113496"1.2低噪声放大器简介PAGEREF_Toc327113496\h2HYPERLINK\l"_Toc327113497"1.3低噪声放大器的发展现状PAGEREF_Toc327113497\h2