外文翻译--数字滤波器的仿真与实现.doc

外文翻译--数字滤波器的仿真与实现.doc

《外文翻译--数字滤波器的仿真与实现.doc》由会员分享，可在线阅读，更多相关《外文翻译--数字滤波器的仿真与实现.doc（14页珍藏版）》请在冰豆网上搜索。

郑州轻工业学院

毕业设计（论文）外文资料翻译

院系

电子信息工程

专业班级

电子信息工程

学生姓名

靖世敏

学号

540901030111

外文出处

附件：

1.外文资料翻译译文（约3000汉字）；

2.外文资料原文（与课题相关的1万印刷符号左右）。

指导教师评语：

　　　　　　　　　　　　　　　　　　　　　　　指导教师签名：

　　　　　　　　　　　　　　　　　　　　　　　　　　年　　月　　日

英文原文

Thesimulationandtherealizationofthedigitalfilter

Withtheinformationageandtheadventofthedigitalworld,digitalsignalprocessinghasbecomeoneoftoday'smostimportantdisciplinesanddoortechnology.Digitalsignalprocessingincommunications,voice,images,automaticcontrol,radar,military,aerospace,medicalandhouseholdappliances,andmanyotherfieldswidelyapplied.Inthedigitalsignalprocessingapplications,thedigitalfilterisimportantandhasbeenwidelyapplied.

1、figuresUniton:

Analoganddigitalfilters

Insignalprocessing,thefunctionofafilteristoremoveunwantedpartsofthesignal,suchasrandomnoise,ortoextractusefulpartsofthesignal,suchasthecomponentslyingwithinacertainfrequencyrange.

Thefollowingblockdiagramillustratesthebasicidea.

Therearetwomainkindsoffilter,analoganddigital.Theyarequitedifferentintheirphysicalmakeupandinhowtheywork.Ananalogfilterusesanalogelectroniccircuitsmadeupfromcomponentssuchasresistors,capacitorsandopampstoproducetherequiredfilteringeffect.Suchfiltercircuitsarewidelyusedinsuchapplicationsasnoisereduction,videosignalenhancement,graphicequilibriuminhi-fisystems,andmanyotherareas.Therearewell-establishedstandardtechniquesfordesigningananalogfiltercircuitforagivenrequirement.Atallstages,thesignalbeingfilteredisanelectricalvoltageorcurrentwhichisthedirectanalogueofthephysicalquantity（e.g.asoundorvideosignalortransduceroutput）involved.Adigitalfilterusesadigitalprocessortoperformnumericalcalculationsonsampledvaluesofthesignal.Theprocessormaybeageneral-purposecomputersuchasaPC,oraspecializedDSP（DigitalSignalProcessor）chip.TheanaloginputsignalmustfirstbesampledanddigitizedusinganADC（analogtodigitalconverter）.Theresultingbinarynumbers,representingsuccessivesampledvaluesoftheinputsignal,aretransferredtotheprocessor,whichcarriesoutnumericalcalculationsonthem.Thesecalculationstypicallyinvolvemultiplyingtheinputvaluesbyconstantsandaddingtheproductstogether.Ifnecessary,theresultsofthesecalculations,whichnowrepresentsampledvaluesofthefilteredsignal,areoutputthroughaDAC（digitaltoanalogconverter）toconvertthesignalbacktoanalogform.

Notethatinadigitalfilter,thesignalisrepresentedbyasequenceofnumbers,ratherthanavoltageorcurrent.

Thefollowingdiagramshowsthebasicsetupofsuchasystem.

Unitreferstotheinputsignalsusedtofilterhardwareorsoftware.Ifthefilterinput,outputsignalsareseparated,theyareboundtorespondtotheimpactoftheUnitisseparated,suchasdigitalfiltersfilterdefinition.Digitalfilterfunction,whichwastoimportsequencesXtransformationintoexportoperationsthroughaseriesY.

Accordingtofiguresfilterfunction24-hourliveresponsecharacteristics,digitalfilterscanbedividedintotwo,namely,unlimitedlonglivelonglivethecorrespondingIIRfilterandthelimitedresponsetoFIRfilters.IIRfiltershavetheadvantageofthedigitalfilterdesigncanusesimulationresults,andsimulationfilterdesignofalargenumberoftablesmayfacilitatesimple.Itistheshortcomingsofthenonlinearphase;Linearphaseifrequired,willusetheentirenetworkphase-correction.Imageprocessingandtransmissionofdatacollectionisrequiredwithlinearphasefiltersidentity.AndFIRlinearphasedigitalfiltertoachieve,butanarbitrarymargincharacteristics.Impactfromthedigitalfilterresponseoftheunitscanbedividedintotwobroadcategories:

theimpactofthelimitedresponse（FIR）filters,andunlimitednumberofshocksto（IIR）digitalfilters.

FIRfilterscanbestrictlylinearphase,butbecausethesystemFIRfilterfunctionextremityfixedattheoriginalpoint,itcanonlyusethehighernumberofbandstoachievetheirhighselectivityforthesamefilterdesignindicatorsFIRfiltercalledbandthanafewhigh-IIR5-10times,thecostishigher,Signaldelayisalsolarger.Butifthesamelinearphase,IIRfiltersmustbenetwork-widecalibrationphase,thesamesectionalsoincreasethenumberoffiltersandnetworkcomplexity.FIRfilterscanbeusedtherecursivemethod,notinalimitedprecisionofashock,andintothehomesandquantitativefactorsofuncertaintyarisingfromtheimpactoferrorsthanIIRfiltersmallnumber,andFIRfiltercanbeusedFFTalgorithms,thecomputationalspeed.ButunlikeIIRfiltercanfilterthroughthesimulationresults,thereisnoread