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predicttheexistenceofelectromagneticwave.IndetailI’velearnedthebasicarithmeticaloperationofelectromagneticwave,thederivationofMaxwellequationsandthePoyntingvectorandguidedelectromagneticwave.ThebasicarithmeticaloperationofelectromagneticHamitonoperator:=e11h

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S=E均匀平面电磁波Uniform neelectromagneticwave:equiphasesurfaceisa neandintheequiphasesurfacethedirectionandthemodulevalueofvectoristhesameatanypoint.电磁波的极化polarizationofelectromagneticWHAT?ThetrajectoryoftheendofthetransientelectricfieldWHY?Becausewhenweresearchtheproblemofreflectionandrefraction,thedirectionofmicrowaveafterreflectionorrefractionisrelatedtothedirectionofpolarization.相速度phasevelocity:Thevelocityof pv (c p 0=4*10-7permeabilityof permittivityofTotalrefraction:Theenergyofwaveistotallytransmittedintotheother垂直极化波verticallypolarizedwave:R02cos11水平极化波horizontalpolarizedwave:R0coscos(;

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If0,thenthetotalreflectionwillTheconductororthemediumofguidedelectromagneticfieldcanguidethetransmissionofelectromagneticwave.Thedevicethatusedtoguideelectromagneticwaveiscalledwaveguide.We’velearnedrectangularwaveguideAsfortheelectromagneticwave,we’velearnedthreekinds,thereTE(TransverseElectric),TM(TransverseElectric),TEM(TransverseElectricandMagneticField)TE:noelectricfieldinthedirectionofpropagation.(Theelectronicvectorexistonlyinthene,whichisperpendiculartothedirectionoftransmission.)TM:nomagneticfieldinthedirectionofpropagation.(Themagneticvectorexistonlyinthene,whichisperpendiculartothedirectionoftransmission).TEM:noelectromagneticfieldinthedirectionofpropagation.(Themagneticvectorandtheelectronicvectorallexistonlyinthene,whichisperpendiculartothedirectionofThetransversemode:Theyrepresentthat,thevectorpresentm/2periodofsinechangeamongthexaxis,n/2periodofsinechangeamongtheyaxis,p/2periodofsinechangeamongthezaxisThiscourseisthebasisofmymajor,I’velearnedseveral yticalmethodto ysistheBasic集总电路定义lumpedThelumpedcircuitareconsistsoflumpedparameterelement,andthelumpedparametermeansthatthesizeofelementisfarsmallerthanthesizeofwordfrequencysize 10* Apointatwhichterminalsofmorethantwocomponentsarejoined.AconductorwithasubstantiallyzeroisconsideredtobeanodeforthepurposeBranch:Thecomponent(s)joiningtwoMesh:AgroupofbrancheswithinanetworkjoinedsoastoformacompleteloopsuchthatisnootherloopinsideitPort Twoterminalswherethecurrentintooneisidenticaltothecurrentoutofthe,阻抗Impedance---Z,电抗Reactance--- Z导纳Admittance---Y,电纳Susceptance---B,YInparallel,Inytical TheprincipleofconservationofelectricchargeimpliesAtanynode(junction)inanelectricalcircuit,thesumofcurrentsflowingintothatnodeisequaltothesumofcurrentsflowingoutofthatnodeorThealgebraicsumofcurrentsinanetworkofconductorsmeetingatapointisThecurrententeringanyjunctionisequaltothecurrentleavingthatjunction.i2+i3=i1+i4 TheprincipleofconservationofenergyimpliesThedirectedsumoftheelectricalpotentialdifferences(voltage)aroundanyclosednetworkiszero,or:Moresimply,thesumoftheemfsinanyclosedloopisequivalenttothesumofthepotentialdropsinthatloop,or:Thealgebraicsumoftheproductsofthesoftheconductorsandthecurrentsintheminaclosedloopisequaltothetotalemfavailableinthatloop.Thesumofallthevoltagesaroundaloopisequaltozero.v1+v2+v3-v4=0Thesuperpositiontheoremforelectricalcircuitsstatesthatforalinearsystem,theresponse(voltageorcurrent)inanybranchofalinearcircuithavingmorethanoneindependentsourceequalsthealgebraicsumoftheresponsescausedbyeachindependentsourceactingalone,wherealltheotherindependentsourcesarerecedbytheirinternalimpedancesturnedoffequivalentmodels.Toascertainthecontributionofeachindividualsource,alloftheothersourcesfirstmustbe"turnedoff"(settozero)by:RecingallotherindependentvoltagesourceswithashortRecingallotherindependentcurrentsourceswithanopenAnylinearelectricalnetworkwithvoltageandcurrentsourcesandonlyscanberecedatterminalsA-Bbyanequivalentvoltagesourceinseriesconnectionwithanequivalent.ThisequivalentvoltageisthevoltageobtainedatterminalsA-BofthenetworkwithterminalsA-Bopencircuited.Thisequivalent isthe obtainedatterminalsA-BofthenetworkwithallitsindependentcurrentsourcesopencircuitedandallitsindependentvoltagesourcesshortAnylinearelectricalnetworkwithvoltageandcurrentsourcesandonlyscanberecedatterminalsA-BbyanequivalentcurrentsourceINOinparallelconnectionwithanequivalentRNO.ThisequivalentcurrentINOisthecurrentobtainedatterminalsA-BofthenetworkwithterminalsA-Bshortcircuited.ThisequivalentRNOistheobtainedatterminalsA-Bofthenetworkwithallitsvoltagesourcesshortcircuitedandallitscurrentsourcesopencircuited. umoutputZLZS,RLRS,XLVCRofcapacitorand i(t)dCuC u(t)dLi zero-stateresponse:thestartstateiszero-inputresponse:theinputoft0isSomethingaboutTheequivalentvoltageorcurrentthatproducethesameamountofenergyinafixedtimewithrealvoltage/current.Theportionofpowerthat,averagedoveracompletecycleoftheACwaveform,resultsinnettransferofenergyinonedirectionisknownasactivepower(sometimesalsocalledrealpowerTheportionofpowerduetostoredenergy,which