小型化宽阻带滤波器设计MINIATURIZEDWIDEBANDFILTERDESIGN摘要时代在不断进步,通信技术也呈现百花齐放形势,各种新技术如雷达技术等都迎来了新突破和新发展,对射频系统也提出了更好的性能标准和要求,微波滤波器是该系统中的重要前端构件,对信号的收发非常重要。滤波器的功能是使有效的信号通过频带,而过滤掉无用的信号。滤波器的设计水平决定了系统的主要指标,例如增益,频带,杂波,并影响接收和发射的质量。滤波器具有小型化、宽阻带、低插入损耗、高频率选择性、高功率电容的特性,这些特性决定了增益、频带、杂波等系统的主要指标,影响了滤波器的质量。另外,为了降低系统成本,减轻重量减小体积,器件和电路的小型化和轻型化越来越重要。本论文以设计小型化,宽阻带,低插损的低通滤波器为目标,内容包括研究背景,滤波器设计的相关理论,基于DGS结构的低通滤波器的设计,基于并联T型枝节的高低阻抗低通滤波器的设计和总结五个部分来分别详细介绍。滤波器工艺的合理选择,是实现无线频率或微波频率的固定带宽的近旁共指标,不仅满足小型化、轻量化,及经济效益的条件,并保证滤波器可以达到工程实用水平。本论文使用了改进哑铃型DGS结构和并联T型枝节SIR结构来达到小型化宽阻带低通的设计目标。一种是在传统哑铃型的两个矩形内刻蚀出一些矩形和矩形缝隙,并用一狭槽相连的改进的哑铃型的DGS结构,另外一种是并联了T型谐振器的高低阻抗结构。前者的阻带达到了6倍通带宽的水平,而后者的过渡带在800MHz左右,且在-20dB内未出现寄生通带。两种结构设计的滤波器均满足了论文设计任务要求的宽阻带和小型化要求,基本达到了工程实用水第I页平。关键词:滤波器;低通;小型化;宽阻带AbstractIntheeraofcontinuousprogress,communicationtechnologyalsopresentsahundredflowersbloomingsituation,avarietyofnewtechnologiessuchasradartechnologyusheredinnewbreakthroughsandnewdevelopments,theradiofrequencysystemhasalsoputforwardbetterperformancestandardsandrequirements,microwavefilterisanimportantfront-endcomponentofthesystem,thesignaltransceiverisveryimportant.Thefunctionofthefilteristopasstheusefulsignalsthroughthefrequencybandandfilterouttheuselesssignals.Theleveloffilterdesigndeterminesthesystem'smainparameters,suchasgain,frequencyband,clutter,andaffectsthequalityofreceptionandtransmission.Thefilterhasminiaturization,widestopband,lowinsertionloss,Thecharacteristicsofhighfrequencyselectivityandhighpowercapacitance,whichdeterminethegain,frequencyband,clutterandothermainindicatorsofthesystem,affectthequalityofthefilter.Inaddition,inordertoreducethecostofthesystem,reducetheweightandreducethevolume,thedeviceandcircuitminiaturizationandlightismoreandmoreimportant.Thispaperaimsatdesigningminiaturized,wide-stopband,low-plug-inlow-passfilter,includingthestudybackground,thetheoryoffilterdesign,thedesignoflow-passfilterbasedonDGSstructure,andthedesignandsummaryofthedesignandsummaryofthehigh-low-passfilterbasedonparallelT-sections.Thereasonablechoiceoffilterprocessisthenear-sidecommonindextorealizethefixedbandwidthofwirelessfrequencyormicrowavefrequency,whichnotonlymeetstheconditionsofminiaturization,lightweightingandeconomicbenefits,butalsoensuresthatthefiltercanreachthepracticallevelofengineering.Inthispaper,thedesigngoalofminiaturizedwide-bandlowpassisachievedbyimprovingdumbbell-typeDGSstructureandparallelT-branchSIRstructure.Oneistoetchsome第II页rectanglesandrectangulargapsintworectanglesofatraditionaldumbbelltype,andtoconnecttheimproveddumbbell-typeDGSstructurewithanarrowslot,andtheotheristoparallelthehighandlowimpedancestructureoftheT-typeresonator.Theformerhasaresistancebandof6timesthepass-throughbandwidth,whil...