使用新型枝节加载阶跃阻抗谐振器的紧凑微带三通带带通滤波器

报告人：宋懿,2016.06.17,Page1,CompactMicrostripTri-BandBandpassFilterUsingNewStubsLoadedStepped-ImpedanceResonator,使用新型枝节加载阶跃阻抗谐振器的紧凑微带三通带带通滤波器,Abstract-摘要：,2,1.Thisletterpresentsanoveltri-bandbandpassfilter(TB-BPF)basedonproposedstubsloadedstepped-impedanceresonator(SLSIR).ThefirstthreeresonantmodesofproposedSLSIRcanbeindependentlycontrolledbytheshortedhighimpedancesectionofSIR,theloadedopenstubandtheloadedshortedstub,respectively,resultingintheindependencyofcentralfrequenciesandreturnlossesofthreepassbands.,中文：本文介绍了一个基于枝节加载阶跃阻抗谐振器的新型三通带滤波器。所提出的这个谐振器能产生三个模式；并且可以通过对阶跃阻抗谐振器的短路高阻抗枝节、加载的开路枝节还有加载的短路枝节的单独调整来实现三个模式的频率单独可控，从而实现滤波器三个通带中心频率和回波损耗的独立可控。,2.Asanexample,aTB-BPFoperatingat0.9/1.8/2.45GHzaredesignedandfabricated.Duetothecancellingeffectofmixedelectricandmagneticcoupling,thevirtualgroundsexistedinSLSIRandtheintroducedembeddedopenstub,sixtransmissionzerosarerealizedaroundthreepassbands,resultinginthehighpassbandselectivityandband-to-bandisolation.,中文：为了体现该谐振器的特性，本文设计并加工了一个中心频率分别在0.9/1.8/2.45GHz的三通带滤波器。由于阶跃阻抗枝节加载谐振器的接地部分和所加载枝节的开路部分存在混合电磁耦合相位抵消，因此在三个通带附近产生了六个传输零点，从而实现通带的高选择性和良好的通带之间的隔离度。,Introduction,1.Planartri-bandbandpassfilter(TB-BPF)withcompactsizeandhighelectricalperformanceisanessentialcomponentinmodernmulti-servicecommunicationsystem.ManyworksonTB-BPFhavebeenrecentlyreported.Thefirstthreeresonantmodesofstubloadedstepped-impedanceresonator(SLSIR)in1andopenstubloadedtri-section/4SIRin2wereproposedtodesignTB-BPFs.However,thelocationsofresonantmodesin1and2needacomplicatedoptimizationtoacquirethedesiredfrequencypositions.,中文：紧凑且电特性良好的平面三通带带通滤波器现代多业务通信系统中的关键器件。近些年来关于三通带滤波器设计在微波界得到广泛报道。文献1首次提出了基于枝节加载阶跃阻抗谐振器的三模谐振器。文献2也提出了将枝节加载的短路的三节四分之一波长阶跃阻抗谐振器用于三通带滤波器设计。但是这两篇文章提出的谐振器，都需要经过复杂的优化过程才能将频率固定在所需要的频点位置。,2.ThedesignapproachesofTB-BPFsin35solvedtheaboveproblem,buttheysufferedfromtherelativelylargecircuitsize.ThisletterpresentsacompactTB-BPFbasedonnewSLSIRswithhighimpedanceratio.Thecentralfrequencies(CFs)andreturnlosses(RLs)ofthreepassbandscanbeindependentlycontrolled.Sixtransmissionzeros(TZs)arerealizedtoimprovethefilterperformance.ATB-BPFoperatingat0.9/1.8GHzforGSMapplication,and2.45GHzforWLANapplicationisdesignedandfabricatedtoverifythevalidityofproposeddesignapproach.,中文：文献35中提出的设计方法很好的解决了上述问题，但是存在设计出的结构尺寸过大的问题。本文提出了一个基于具有高阻抗比特性的新型枝节加载阶跃阻抗谐振器。所实现的三个通带的中心频率还有回波损耗都具有独立可控的特性。并且还获得了六个传输零点，有效的改善了通带的选择性。最后设计并加工了一款中心频率为0.9/1.8GHz可用于GSM通信和中心频率为2.45GHz（用于无线通信）的三通带滤波器，从而证明所提出的方法可行性。,II.ProposedSLSIR,Fig.1(a)showsthetransmissionlinemodelofproposedSLSIR.Zi(i=1,2,3,4)andj(j=1,2,3,4,t)representimpedanceandelectricallength,respectively.Theinputadmittanceseenfromtheloadedpointcanbederivedas:,Fig.1(a)showsthetransmissionlinemodelofproposedSLSIR.Zi(i=1,2,3,4)andj(j=1,2,3,4,t)representimpedanceandelectricallength,respectively.Theinputadmittanceseenfromtheloadedpointcanbederivedas:,中文：图1给出了该谐振器的传输线模型。Zi(i=1,2,3,4)andj(j=1,2,3,4,t)分别表示阻抗和电长度，可以推导出从枝节加载点看进去的导纳公式如下：,Withintheinterestedfrequencyrange,therearethreeresonantmodesfp1,fp2andfp3whicharedeterminedbyY=0.Moreover,threepotentialTZsTZVG1,TZVG2andTZVG3locatedattheuppersidesofthreeresonantmodescanbeobserved,mainlyduetothevirtualgroundsexistedinSLSIR(Y=).SincethedesignparametersofSLSIRarepriortomeettherequiredfrequencypositionsofthreeresonantmodes,theTZsduetoY=cannotbetunedfreely.,中文：在有研究兴趣的频带内，可以推导Y=0来确定fp1,fp2和fp3三个谐振频率。同时，因为谐振器的虚拟接地端，在三个模式的上边带部分出现了三个传输零点。因为在滤波器设计确定结构参数的时候，通常优先选择先确定所需的谐振频点，所以零点不能实现独立可控。,AsshowninFig.2(a)(c),alargervalueofKisbenefitforcontrollingthecorrespondingresonantmodeindependently.Fig.2(a)(c)alsoshowthatfp1,fp2andfp3canbeindependentlycontrolledby1,3and4,respectively.Inthisdesign,K=4.9isselectedandZ219canbecalculated.AsshowninFig.2(d),thedifferentloadedpointtalsohasminoreffectonfp1,fp2,andfp3.Inthisdesign,thetappedpointoffeedinglineisselectedattheloadedpoint.,中文：从图2的(a)(c)可以发现，K的值越大越有利于实现相应频率的独立可控。根据图2的(a)(c)还可以发现fp2和fp3可以分别通过改变1,3和4得大小来实现单独可控。在实际设计当中，K的值选为1，从而可以计算的Z219。如图2（d）所示加载位置t的不同对fp1,fp2和fp3有微小的影响。设计过程中，本文将馈线的抽头位置选在枝节加载节点处。,AnovelTB-BPFwithindependentlycontrolledCFs(centerfrequencies)andinbandRLsarepresentedbyusingproposedSLSIR.SixTZsgeneratedbythecancellingeffectofMEMC,virtualgroundsexistedinSLSIRandEOSimprovethepassbandselectivityandband-to-bandisolationsignificantly.ThefabricatedTB-BPFalsoexhibitacompactsizeandwideupperstopband.ThesemeritsmakethenewlyproposedTB-BPFattractiveinmodernmulti-servicetransceiver.,IV.C