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1、Chapter4ElectromagneticFieldandWaveOutline4.1ElectromagneticFieldsTheory4.2Antenna7/28/20211《电子信息与通信工程专业英语》4.1ElectromagneticFieldsTheoryOutlineMaxwell’sequationsCurrentcontinuityequationConstitutiverelationsBoundaryconditionsPowerandenergy7/28/20212《电子信息与通信工程专业英语》Terminologyvectorn.[数]向量,矢量,带菌者vt.
2、无线电导引scalarn.数量,标量adj.分等级的,数量的,标量的positionvectorn.位矢,方位向量,位置矢量fluxn.[物]流量,通量,涨潮,变迁vi.熔化,流出vt.使熔融,用焊剂处理contourn.轮廓,周线,等高线emfabbr.电动势(electromotiveforce)Stockes’theoremn.斯托克斯定理divergencetheoremn.散度定理conductioncurrentn.传导电流displacementcurrentn.位移电流7/28/20213《电子信息与通信工程专业英语》solenoidalfieldsn.螺线管磁场,管形场co
3、ntinuityequationn.连续性方程constitutiverelationn.本构关系isotropicadj.等方向性的,各向同性的dielectricconstantn.介电常数relativepermeabilityn.相对磁导率conductivityn.传导性,传导率anisotropicadj.各向异性的tensorn.张量,张肌7/28/20214《电子信息与通信工程专业英语》In1864,JamesClerkMaxwellproposedoneofthemostsuccessfultheoriesinthehistoryofscience.Inafamousmem
4、oirtotheRoyalSociety,hepresentednineequationssummarizingallknownlawsonelectricityandmagnetism.Bypostulatingtheneedforanadditionaltermtomakethesetofequationsself-consistent,Maxwellwasabletoputforthwhatisstillconsideredacompletetheoryofmacroscopicelectromagnetism.Toformacompletefieldtheoryweneedasour
5、cefield,amediatingfield,andasetoffielddifferentialequations.Thisallowsustomathematicallydescribetherelationshipbetweeneffect(themediatingfield)andcause(thesourcefield).IntroductionTexttour7/28/20215《电子信息与通信工程专业英语》InMaxwell’sequations,thesourcefieldconsistsofthevectorfield(thecurrentdensity)andthesc
6、alarfield(thechargedensity),themediatingfieldistheelectromagneticfieldconsistingofthesetoffourvectorfields,,and.7/28/20216《电子信息与通信工程专业英语》=electricfieldintensity(vector),volts/meter(V/m)=magneticfieldintensity(vector),ampere/meter(A/m)=electricfluxdensity(vector),coulombs/meter2(C/m2)=magneticfluxde
7、nsity(vector),webers/meter2(Wb/m2)=electriccurrentdensity(vector),amperes/meter2(A/m2)=electricchargedensity(scalar),coulombs/meter3(C/m3)7/28/20217《电子信息与通信工程专业英语》Alltheabovequantities,intime-varyingfields,