电磁理论基础文档.ppt

电磁理论基础Foundation of EM Theory Chapter 0 Yu Zhiyuan 2010.5 The Important of EM Theory 电磁理论是信息科学的基础。 而信息科学，生命科学与材料科学是国民经济三大基础科学。 信息产业： 1。移动通信; 2。网络技术：interenet, wireless Access; Wireless mesh sensor network; Physical Dstribution network or Logistics network 3。集成电路 Integrate Circuits The Contents 1.Maxwell’s Equations; 2.Boundary Condition; 3. Constitutive relations; 4. conversation of energy? in EM and Poyntings theorem; 5.Wave equations; 6. Some Laws and theorems 7. The Potential Theory 1.Maxwell’s Equations 1.　Differential form 微分形式 2. Integral form 积分形式 3. Maxwell’s Equation in S-Domain 　　　S域中的麦克斯韦方程 4。　时域表达式 5。　频域表达式 6。　静场　 Boundary Condition 不同媒质边界上的边界条件 The Boundary Condition under Numerical Computation 1. Some thing same as above; 2. ABC: Absorbering Boundary Condition; 3. Boundary Condition for wave equation For Wave equation 1. Dirichlet condition may be specified as Φ(r) = 0 2. Neumann boundary condition is specified as ?Φ(r)/?n =f(s), on contour C 3. 　　　　　　　　混合边界条件 3. Constitutive relations 这里 和为3×3张量.本构关系确定了所涉及的媒质的特性.由上两式所确定的媒质称为双各向异性媒质.这样的媒质在 电场中或在磁场中,将被同时极化和磁化. loss in dielectrics is known as the loss tangent of the medium.电极化强度P和电极化率?e [kai] 电极化强度M和电极化率?m [kai] p5 Poynting Theorem Wave Equation Loss media Lossless media Homogeneous equation Wave in Loss Media 一维有耗波方程MatLab数值模似 Some Laws and theorems 1. Superposition Principles ; 2. Duality; 3. Uniqueness of solutions to Maxwell’s equations; 4. Reciprocity, 5. Image Theory. The Potential Theory 1.Vector potential A. Lorentz guage. B. Coulomb’s guage. C. Velocity guage * Perfect Conductor 分别为电容率张量和磁导率张量.在各向异性的媒质中,电场不再与电通量D相平行;磁场强度也不再与磁通量B相平行; Loss material Where 左边为体积向外的电磁辐射能； 右边第一项为体积内的磁储能随时间变化率； 右边第二项为体积内的电储能随时间变化率； 右边第三项为体积内的导电损耗－焦耳热； 整个式子表示（电磁）能量守恒。 S=E?H　为坡印廷矢量　Poynting vector Define k as the wave vector, the magnitude of which is the phase coefficient k, and