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1、命两)学/学照倒学院NORTHWESTERNPOLYTECHNICALUNIVERSITYMINGDECOLLEGE本科毕业设计(论文)外文翻译原文题目四号TimesNewRoman译文题目四号宋体系另fj四号宋体专业名称四号宋体学生姓名四号宋体指导教师四号宋体毕业时间2016年*月*曰原文题目Historyofthedevelopmentofthefilter译文题目滤波器的发展史作者译名国籍原文出处外文翻译:In1917,theU.S.andGermanscientistswereinventedtheLCfilters,thefollowingyearledtheUnitedStates
2、firstmultiplexingsystemstoappear.The1950smatureofpassivefilter.Sincetheswiththecomputertechnology,integratedprocessandmaterialindustrydevelopment,thefilterdevelopmentonanewlevel,andlowpowerconsumption,highprecision,towardsmallvolume,multi-function,stableandreliableandinexpensiveeffort,includingsmall
3、volume,multi-function,highprecision,stableandreliableasa70sthemainattackdirectioninthefuture.1,FilterdevelopmentintroductionAllhavetheabilitytosignalprocessingdevicescanbecalledafilter.Inthemoderntelecommunicationsequipmentandallkindsofcontrolsystem,thefilterarewidely;Ofalltheelectroniccomponents,th
4、euseofthemost,themostcomplextechnologyisfilter.Themeritsofthefilterdirectlydetermineproductquality,therefore,tofilterintheresearchandproductionhasbeenonforallcountries.CauseRCactivefilter,digitalfilters,switchcapacitancefilterandthechargetransferoftherapiddevelopmentoffilter,tothe70s,theaboveseveral
5、filtermonolithicintegrationhasbeendevelopedandapplied.Inthe80s,specializedinallkindsofnewtypefilterresearch,andstrivetoimproveperformanceandgraduallyexpandthescopeofapplication.Inthe90stonowmainlydevotestotheofallkindsfilterusedinallkindsofproductdevelopmentandresearch.Ofcourse,tofiltertheresearchco
6、ntinuestoitself.Ourcountrywideusefilteris50sandthereismainlyusedinroadfilterandreportwaywordsfilter.Afterhalfacenturyofdevelopment,Chinafilterinthedevelopment,productionandapplicationalreadyintotheinternationaldevelopmentpace,butduetothelackofspecializedresearchinstitutions,ntegrationprocessandmater
7、ialindustrycan'tkeepup,causingmanynewfilterdevelopmentinChinaandinternationaldevelopmentapplicationforashortdistance.2,TheclassificationofthefilterTherearedifferentkindsoffilterclassification,generallyhasthefollowingseveralkinds.(1)AccordingtodealwithsignaltypeclassificationAccordingtotheprocess
8、ingsignaltypeclassification,maybeclassifiedasanalogfilteranddiscretefiltertwokindsbig.Onesimulationandcanbedividedintoactivefilter,passive,threedifferentclassification;Discretefilterandcanbedividedintodigital,samplingsimulation,mixedthreeclassification.Ofcourse,eachclassificationandcancontinuetopoin
9、tsdown,inshort,theirclassificationcanformatreestructure,infactsomefilterishardtobewhichkindof,suchasswitchingcapacityfiltercannotonlybelongstothesamplingsimulationfilter,andbelongtothemixingfilters,stillcanbelongtoactivefilter.Therefore,wedon'thavethe"accurate"demandingclassification,j
10、ustletpeopleknowaboutthescopeofthefiltertypes,ageneralconceptwilldo.(2)AccordingtochoosephysicalquantitiesclassificationAccordingtochoosephysicalquantitiesclassification,filtercanbedividedintofrequencyselection,amplitudeselection,timetochoose(suchasthewordsofPCMsignals)andinformationchoice(forexampl
11、ematchingfilter),andotherfourkindsoffilter.(3)ByfrequencybandpassrangeclassificationAccordingtotheclassificationwithfrequencyrange,filtercanbedividedintolowpass,qualcomm,band-pass,takeresistance,allthefivecategories,andcombformbandpassfilterbelongtostopfilterandbelt,becauseithasperiodicbandpassandst
12、opband.Filtersortisvarious,somearewellknown,somemaynotbewhatwearefamiliarwith,introducedinrecentyearsthedevelopmentofseveralfiltersoon.3,ActivefilterBythefollowingactivepowerfiltersomeactivecomponents:operationalamplifier,thenegativeresistance,capacitanceandinductance,negativenegativefrequencyrheost
13、at(FDNR)generalizedimpedancetransformer(GIC),negativeimpedancetransformer(NIC),arempedancetransformer(PIC),negativeimpedanceinversiondevice(NII),areimpedancenversiondevice(PII),fourkindsofcontrolledsource,inaddition,thereisaverysicksonandsonzerocomponents.1965monolithicintegratedoperationalamplifier
14、advent,foractivefilteropenedupbroadprospects.Intheearly70s,activefilterdevelopmentconspicuous,1978singlechipRCactivefiltercomeout,forfilterintegratedintowelcomestep.Duetotheop-amptheripplesofgainandphase-shiftareofthefrequencyoffunction,thislimitstherangeoffrequenciesRCfilter,generalworkingfrequency
15、forabout20kHz,aftercompensation,workingfrequencyalsolimitedto100kHzlessthan.1974yearsproducedmorehighfrequencyRCactivefilter,andcausetheworktofrequencyofGB/4(GBforop-ampgainandbandwidthoftheproduct).DuetotheexistenceofR,integratedprocesstocausedifficulties,andheappearedactiveCfilter:isbyCandop-ampfi
16、ltercomposition.Sucheasytointegration,moreimportantistoimprovetheprecisionofthefilter,becausetheperformanceofthefilteractiveCdependsonlyontheratioofcapacitance,hasnothingtodowithcapacitanceabsolutevalue.Butitisamajorproblem:becauseeachbranchcomponentsarecapacitance,soop-ampnodcfeedbackchannel,thatst
17、abilityisadifficultproblem.1982byGeiger,AllenandNgowithcontinuousswitchproposedresistance(SR)toreplaceactiveRCfiltertheelectricalresistanceR,constitutestheSRCfilter,itstillbelongstothesimulationfilter.Butduetothepresetcircuitandcomplexofthephaseoftheclock,thefilterdevelopmentprospectisnotbig.Inshort
18、,bytheRCactivefilterisaprototypeofallkindsofvariantactivefiltertoremoveinductors,smallvolume,Qvaluecanreach1000,overcometheRLCpassivefilterisbig,Qvalueofsmallfaults.Butitstillhasmanytopicneedsfurtherresearch:idealop-ampandpracticalcharacteristicsofthedeviation;Duetotheactivefilterhybridintegratedpro
19、cessimprovement,monolithicintegratedneedsfurtherresearch;Applicationlineartransformmethodtoexploretheleastanactiveelementoffiltersneedtocontinuetoexplore;Componentsoftheabsolutevalueoftolerance,theexistenceofprecisionandperformanceinfluencefiltertheproblemisstillnotsolved;BecauseRexist,integrationof
20、chiptheareaislarge,resistanceerror(20%30%),poorlinearitydisadvantages,makinglargescaleintegratedstillhavingdifficulty.Althoughtherearesomanyquestions,RCactivefiltertheoryandapplicationisstillinsustainabledevelopment.4,Switchcapacitancefilter(SCF)The1980stechnologyreformamajorissueistherealizationofv
21、ariouselectronicsysteminargescaleintegration(LSI).Usemostfiltersbecome"tiger",RCactivefiltercan'tachieveLSI,passivefilterandnottomentionthemechanicalfilter,andso,peoplecanonlyadditionalmonarchnewsize.50stherehasbeenputforwardtheconceptofSCF,becauseatthattimeintegrationprocessdoesn'
22、tpass,anddidnotcausetheattentionofpeople.In1972,theUnitedStatesacallFriedscientistspublishedwithaswitchandcapacitancesimulationresistanceR,saidtheperformanceoftheSCFdependsonlyontheratioofcapacitance,hasnothingtodowithcapacitanceabsolutevalue,sojustcausetheattentionofpeople.In1979,somedevelopedcount
23、riesmonolithicSCFhasbecomeacommodity(arehighlyconfidentialtechnology).NowSCtechnologymature.TheprocesstorealizetheMOSSCF,isrecognizedasthe80snetworktheoryandintegratedprocessofamajorbreakthrough.ThecurrentMOScapacitanceforageneralmethodto100withinpFskin,ithasa(10100)x10-6/Vvoltagecoefficientand(1010
24、0)x10-6/temperaturecoefficient,thetwocoefficientisclosetoidealrealmalmost.SCFhasthefollowingsomeadvantages:SCFcanbelargescaleintegrated;SCFhighprecision,becauseitsperformancedependsontheratioofcapacitance,andtheratioofcapacitanceMOSerrorlessthanoneoveronethousand;Thefunctionismuch,almostallelectroni
25、ccomponentsandfunctionsaretheSCtechnologytorealize;Digitalfilterthansimple,becausedonotneedA/DandD/Atransformation;Functionissmall,candolessthan10mW.TheapplicationoftheSCFtoaudiorangeapplicationasthemainbody,theworkin100kHzfrequencywithin.Insignalprocessingapplicationsare:SPCSCF,analogsignalprocessi
26、ng,vibrationanalysis,adaptivefilter,music,resonancespectrum,comprehensivelanguageintegrateddevice,toneselection,soundscoding,audioanalysis,equalizer,modem,phaselockedcircuit,discreteFouriertransformInshort,SCF,medicalinstrumentsinthemetermeasuringanddataorinformationprocessing,andmanyotherareashaveb
27、roadapplicationprospect.Inourcountry,some1978graduatestudentsbegantomentorandconductedtheresearchwork,andreallycausepeopletopayattentiontois1980yearslater.Tsinghuauniversityhasmade1983singlechipSCF,chengduacademyofengineeringandjointfactory,developedasinglepieceofSCF.NowthekeyistouseMOSprocessrealiz
28、eSCFandapplicationofaproblem,becauseusersdon'tknowit,inourcountrytheapplicationofSCFisnotpopular.5,SCFandmanyoftheissuesneedtoberesearched(1)Theop-ampandcontroloftheMOSswitchsamplingfrequencylimit,makestheSCFcanonlywithinthescopeoftheaudioapplications.Inrecentyears,althoughappearhavenoop-ampofth
29、eSCcircuit,butbecausesamplingfrequencyrestrictions,thehighestrateofworkonlyin1MHzwithin.(2)TheMOSswitchthechannelofresistanceandtheidealop-ampcharacteristics,allcanmakeSCFcauseerrors.(3)SwitchcapacitanceitselftotheparasiticcapacitanceSCFfrequencyresponsedistortionoccurred.(4)MOSswitchandMOSop-ampthe
30、rmalnoisemakeSCFdynamicrangewaslimited.FinallyintheprocesstoachievetheMOSSCF,becauseitistime-varyingnetwork,wanttouseaccuratesimulationcomponentsdivisionisnotpossible,such,designperfectCADtechnologyisthesolutionofthisproblemonlymeans.Inaddition,thesensitivityanalysis,noiseanalysisweremanyissuesneedt
31、oberesearched.6,Severalnewdigitalfilter(DF)(1)TheadaptiveDFTheoptimalcontrolandadaptivecontrolandself-learningcontrolwererelatedtomanyparameters,multivariatecomplexcontrolsystem,allbelongtothemoderncontroltheoryofresearch.AdaptiveDFhastheverystrongself-learning,sincethetrackingfunction.Itontheradara
32、ndsonarbeamforming,slowlynoisesuppression,noisesignalprocessing,thecommunicationchanneladaptiveequilibrium,theechoofthelongdistancetelephoneoffset,etchavegainedwideapplication,andpromotethedevelopmentofmoderncontroltheory.AdaptiveDFhasthefollowingafewsimplealgorithm:W-LMSalgorithm,M-LMSalgorithm,TDO
33、algorithm,differenceLMSalgorithmandC-LMSalgorithm.(2)ThepluralDFIntheinputsignalfornarrowbandsignalprocessingsystem,oftenbypluralDFtechnology.Inordertoreducethesamplingrateandsavesignalcontainsalloftheinformation,canuseorthogonaldoubleroaddetectionmethod,removenarrowbandsignalofthecomplexenvelop,and
34、thenthroughtheA/Dtransformation,willthecomplexenvelopintocomplexsequenceforprocessing,thesignalprocessingsystemisforpluralDF.Ithasmanyfunctions:MTIthesuppressiondopplerradarwithdoppler-shiftclutterinterference;DigitalcommunicationnetworkandsimulationcommunicationnetworkmoreroadbetweenTDM/FDMsignaltr
35、ansformationaftermeet.(3)ThemultidimensionalDFInimageprocessing,earthquake,oilexplorationdataprocessingallusemultidimensionalDF(commonlyusedis2dDF),thedesignofthemultidimensionalDF,oftenadDFoptimizationdesigntomulti-dimensionalDFdirectmarketing.Forfuzzyandrandomnoisenterference2dimageprocessing,mult
36、idimensionalDFalsocanplayaverygoodeffect.Inaddition,stillwaveDF,itiseasytorealizelarge-scaleintegrated,facilitatepassiveandactivepowerfilternetworkdigitalsimulation.Therefore,isattentionbypeopleandstudied.ForDFremainstobesubjectsofstudy:coefficientsensitivity,roundingnoiseandlimitcycle,thestabilityo
37、fthemultidimensionalinversetofilter,allkindsofhardwareandsoftwareimplementationofDFresearchandsoon.Inshort,DFindigitalsignalprocessingtechnologyisveryimportantpositionnpossession,foritsresearch,productionandapplication,etcallisverymeaningful.7,OthernewfilterInordertoadapttoallkindsofneed,theemergenc
38、eofabatchofnewfilter,presentedherehasbeenwidelyusedseveraltypesoffilters.(1)ElectriccontrolprogrammingCCDhorizontalfilter(FPCCDTF)Acharge-coupleddevice(CCD)fixedweightedtransversefilter(TF)insignalprocessing,theperformanceandcostallcanwithdigitalfilterandallkindsofsignalprocessingunit).Thisfilterism
39、ainlyusedforadaptivefilter;P-NsequenceandChirpwaveformofmatchedfilter;Generalizationoffrequencydomainfilterandrelatedproductoperation;Speechsignalandthephaseequilibrium;Phasearraysystemsbeamsynthesisandtelevisionsignals(2)CystalfilterItistomeetwiththesingletechnologyanddeveloped.Inthe1970s,theintegr
40、atedproductionofcrystalfilter,makeitofdevelopmenthavealeap.Inthelasttenyears,crystalfilterbelowtosomeresearch:toachievethebestdesign,besideshavingthefinechooseoutside,stillhavegoodtimedomainresponse;Seeknewmaterials;Extendedworkingfrequency;Modificationtechnology,madeittotheintegrateddevelopment.Iti
41、swidelyusedinmultiplexedsystemasthecarrierfilter,insendingandreceivingtheletter,withthesinglecommunicationmachineasfrequencyselectivefilter,inaspectrumanalyzerandsonardeviceasintermediatefrequencyfilters.(3)SurfaceacousticfilterItistheidealuhfdevices.Itsamplitudefrequencycharacteristicsandphasechara
42、cteristicrespectivelycontrol,soastomeettherequirements,anditalsohassmallvolume,longtimegoodstabilityandsimpleprocessetc.Characteristics.Usuallyusedin:TVbroadcasttransmitterasresidualsidebandfilter;Thecolortelevisionreceiversoftuningsystemsurfacecombformfilter.Inaddition,inthedefensesatellitecommunic
43、ationsystemshasbeenwidelyadopted.Surfaceacousticfilteriselectronicsandacousticsproductofintegrationof,andcanbeintegrated,so,itallpassivefilterinthemostpromising.Variousnewfiltertooisvarious,somewhere,nolongerdescribedthem.OurcountryatpresenttheapplicationofvariousfilterproportionOurcountry'sexis
44、tingtypesoffiltersandthefrequencyofthecoveredhasbasicallysatisfyexistingtelecommunicationsequipment.Fromtheoverall,ourcountryactivefilterdevelopmentthanpassivefilterslow,hasnotbeenalotofproductionandapplication.Fromthefollowingproductionapplicationproportionofvarioustypesoffilterscanbeseen,theapplic
45、ationofthe:LCfilters50%;Crystalfilteraccountedfor20%;Mechanicalfilteraccountedfor15%;Ceramicfilterharmonicsurfaceeachaccountedfor1%;Therestaccountedfor13%ofallkindsoffilter.Fromtheapplicationscale,electronicproductsinChinatorealizethelarge-scaleintegrated,filterintegrationisstillaimportanttopic.Alon
46、gwiththedevelopmentoftheelectronicindustry,tofiltertheperformancerequirementsofmoreandmorehigh,functionmoreandmore,andaskedthemtointegrationdevelopmentdirection.Ourcountryfilterdevelopmentandproductionoftheaboverequirementsandfar,inordertoreducethatgap,electronicengineeringandscientificandtechnologi
47、calpersonnelresponsibleforthemajorhistoricalresponsibility.中文译文:1917年美国和德国科学家分别发明了LC滤波器,次年导致了美国第一个多路复用系统的出现。20世纪50年代无源滤波器日趋成熟。自60年代起由于计算机技术、集成工艺和材料工业的发展,滤波器发展上了一个新台阶,并且朝着低功耗、高精度、小体积、多功能、稳定可靠和价廉方向努力,其中小体积、多功能、高精度、稳定可靠成为70年代以后的主攻方向。一、滤波器发展引言凡是有能力进行信号处理的装置都可以称为滤波器。在近代电信设备和各类控制系统中,滤波器应用极为广泛;在所有的电子部件中,使用
48、最多,技术最为复杂的要算滤波器了。滤波器的优劣直接决定产品的优劣,所以,对滤波器的研究和生产历来为各国所重视。导致RC有源滤波器、数字滤波器、开关电容滤波器和电荷转移器等各种滤波器的飞速发展,到70年代后期,上述几种滤波器的单片集成已被研制出来并得到应用。80年代,致力于各类新型滤波器的研究,努力提高性能并逐渐扩大应用范围。90年代至现在主要致力于把各类滤波器应用于各类产品的开发和研制。当然,对滤波器本身的研究仍在不断进行。我国广泛使用滤波器是50年代后期的事,当时主要用于话路滤波和报路滤波。经过半个世纪的发展,我国滤波器在研制、生产和应用等方面已纳入国际发展步伐,但由于缺少专门研制机构,集成
49、工艺和材料工业跟不上来,使得我国许多新型滤波器的研制应用与国际发展有一段距离。二、滤波器的分类滤波器有各种不同的分类,一般有如下几种。(1)按处理信号类型分类按处理信号类型分类,可分为模拟滤波器和离散滤波器两大类。其中模拟滤波器又可分为有源、无源、异类三个分类;离散滤波器又可分为数字、取样模拟、混合三个分类。当然,每个分类又可继续分下去,总之,它们的分类可以形成一个树形结构,实际上有些滤波器很难归于哪一类,例如开关电容滤波器既可属于取样模拟滤波器,又可属于混合滤波器,还可属于有源滤波器。因此,我们不必苛求这种“精确”分类,只是让人们了解滤波器的大体类型,有个总体概念就行了。(2)按选择物理量分
50、类按选择物理量分类,滤波器可分为频率选择、幅度选择、时间选择(例如PCM制中的话路信号)和信息选择(例如匹配滤波器)等四类滤波器。(3)按频率通带范围分类按频率通带范围分类,滤波器可分为低通、高通、带通、带阻、全通五个类别,而梳形滤波器属于带通和带阻滤波器,因为它有周期性的通带和阻带。滤波器种类繁多,有些是众所周知的,有些可能不为大家所熟悉,下面着重介绍近年来发展很快的几种滤波器。三、有源滤波器有源滤波器由下列一些有源元件组成:运算放大器、负电阻、负电容、负电感、频率变阻器(FDNR)、广义阻抗变换器(GIC)、负阻抗变换器(NIC)、正阻抗变换器(PIC)、负阻抗倒置器(NII)、正阻抗倒置
51、器(PII)、四种受控源,另外,还有病态元件极子和零子。1965年单片集成运算放大器问世后,为有源滤波器开辟了广阔的前景。70年代初期,有源滤波器发展引人注目,1978年单片RC有源滤波器问世,为滤波器集成迈进了可喜的一步。由于运放的增益和相移均为频率的函数,这就限制了RC有源滤波器的频率范围,一般工作频率为20kHz左右,经过补偿后,工作频率也限制在100kHz以内。1974年产生了更高频的RC有源滤波器,使工作频率可达GB/4(GB为运放增益与带宽之积)。由于R的存在,给集成工艺造成困难,于是又出现了有源C滤波器:就是滤波器由C和运放组成。这样容易集成,更重要的是提高了滤波器的精度,因为有
52、源C滤波器的性能只取决于电容之比,与电容绝对值无关。但它有一个主要问题:由于各支路元件均为电容,所以运放没有直流反馈通道,使稳定性成为难题。1982年由Geiger、Allen和Ngo提出用连续的开关电阻(SR)去替代有源RC滤波器中的电阻R,就构成了SRC滤波器,它仍属于模拟滤波器。但由于采用预置电路和复杂的相位时钟,使这种滤波器发展前途不大。总之,由RC有源滤波器为原型的各类变种有源滤波器去掉了电感器,体积小,Q值可达1000,克服了RLC无源滤波器体积大,Q值小的缺点。但它仍有许多课题有待进一步研究:理想运放与实际特性的偏差的研究;由于有源滤波器混合集成工艺的不断改进,单片集成有待进一步
53、研究;应用线性变换方法探索最少有源元件的滤波器需要继续探索;元件的绝对值容差的存在,影响滤波器精度和性能等问题仍未解决;由于R存在,集成占芯片面积大,电阻误差大(20%30%),线性度差等缺点,使大规模集成仍然有困难。尽管有这么多问题,RC有源滤波器的理论和应用仍在持续发展中。四、开关电容滤波器(SCF)20世纪80年代技术改造一个重大课题是实现各种电子系统全面大规模集成(LSI)。使用最多的滤波器成为“拦路虎”,RC有源滤波器不能实现LSI,无源滤波器和机械滤波器更不用说了,于是,人们只能另辟新径。50年代曾有人提出SCF的概念,由于当时集成工艺不过关,并没有引起人们的重视。1972年,美国
54、一个叫Fried的科学家发表了用开关和电容模拟电阻R,说SCF的性能只取决于电容之比,与电容绝对值无关,这样才引起人们的重视。1979年一些发达国家单片SCF已成为商品(属于高度保密技术)。现在SC技术已趋成熟。SCF采用MOS工艺加以实现,被公认为80年代网络理论与集成工艺的一个重大突破。当前MOS电容值一般为几皮法至100pF之内,它具有(10100)X10-6/V的电压系数与(10100)X10-6/C的温度系数,这两个系数几乎接近理想的境界。SCF具有下列一些优点:SCF可以大规模集成;SCF精度高,因为其性能取决于电容之比,而MOS电容之比的误差小于千分之一;功能多,几乎所有电子部件
55、和功能均可以由SC技术来实现;比数字滤波器简单,因为不需要A/D、D/A转换;功能小,可以做到小于10mW。SCF的应用以声频范围应用为主体,工作频率在100kHz之内。在信号处理方面的应用有:程控SCF、模拟信号处理、振动分析、自适应性滤波器、音乐综合、共振谱、语言综合器、音调选择、语声编码、声频分析、均衡器、解调器、锁相电路、离散傅氏变换总之,SCF在仪表测量、医疗仪器、数据或信息处理等许多领域都有广泛的应用前景。在我国,1978年有的导师和在校研究生开始进行这项研究工作,真正引起人们重视是1980年以后。1983年清华大学已制成单片SCF,成都工程学院与工厂联合,也研制成单片SCFo现在关键是用MOS工艺实现SCF及推广应用问题,由于用户还不了解它,在我国SCF的应用还没有普及。五、SCF还有许多课题有待研究(1)由于运放和控制MOS开关的采样频率所限制,使得SCF只能在音频范围内应用。近年虽然出现无运放的SC电路,但由于采样频率
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