【作者】 李颖；

【导师】 罗建书；

【作者基本信息】 国防科学技术大学 ， 数学， 2012， 博士

【摘要】 随着电子信息技术的快速发展,电子系统自身及其所处的电磁环境日趋复杂.复杂电子系统的电磁耦合是当前电磁兼容领域中的研究热点,本文基于电磁拓扑理论和方法对矩形腔孔缝耦合进行了分析与计算.主要工作如下：1.基于Maxwell方程推导了一种新的双导线传输线耦合模型,这是一种关于散射电压和散射电流的耦合模型.用解析方法证明了在解决场线耦合问题时这个新的耦合模型与Agrawal、Taylor以及Rachidi耦合模型是等价的.2.提出了计算矩形腔孔缝耦合的转移函数法.在孔缝等效磁流已知的情况下,利用并矢格林函数法、标量波函数法和位函数法等三种方法获得了内转移函数,并且证明了这三种方法得到的内转移函数是相同的.为得到矩形腔外部散射场,利用位函数法获得了外转移函数.为确定转移函数中的等效磁流,对于窄缝,采用了等效磁偶极子法;对于宽缝,采用了三角脉冲函数法.从而得到了内外场的转移关系式.通过数值比较,验证了转移函数法的有效性.3.对于带孔缝单层内置传输线矩形腔问题,提出了计算终端响应的两种方法.一种是基于转移函数的缝线耦合Agrawal耦合模型法,另一种是基于传输线拓扑网络的缝线耦合网络BLT方程法.通过数值方法验证了Agrawal耦合模型法与网络BLT方程法的有效性.4.对于带孔缝双层内置传输线矩形腔问题,提出了计算终端响应的两种方法.这两种方法均基于传输线拓扑网络,分别是EMT1法和EMT2法. EMT1方法是利用网络BLT方程、内腔的耦合场以及Agrawal耦合模型计算内置传输线响应的方法. EMT2方法是先用网络BLT方程求外腔体内的响应电压再用网络BLT方程求内置传输线响应的方法.两种方法的数值结果进行比较后,结果非常吻合.5.研究了带多孔缝矩形空腔模型和带多孔缝内置传输线矩形腔模型的电磁交互作用,提出了基于转移函数的线性叠加法和基于电磁拓扑的多步迭代算法.更多还原

【Abstract】 With the fast development of the electric information technology, the electricsystems themselves and the electromagnetic environment have become more andmore complex. Nowadays, the electromagnetic coupling of complicated electric sys-tems has become an interesting and hot issue in the area of electromagnetic com-patibility. In this thesis, coupling analysis and computation of a rectangular cavitywith apertures are studied based on the electromagnetic topology method. Themain results are included as follows.1. A new transmission line coupling model is deduced from Maxwell’s equa-tions. It is a kind of coupling model with respect to the scattered voltages andcurrents. Using analytical method, the equivalence among this new coupling model,the Agrawal, Taylor and Rachidi coupling models for solving feld-to-line couplingproblems is proved.2. A method of the transfer functions is proposed to compute aperture couplingof a rectangular cavity. On the assumption that aperture equivalent currents areknown, expressions of the internal transfer functions are generated by the methodof the dyadic Green’s functions, the method of the scalar wave functions and thatof the potential functions, respectively. The equivalence among these three kinds ofexpressions is proved. We still use the method of the potential functions to obtainexpressions of the external transfer functions for obtaining the scattered electromag-netic feld outside the cavity with apertures. In order to determine the equivalentcurrents on the aperture, the equivalent magnetic dipole method is developed forthin aperture, while the triangular and pulse functions method is developed for thickaperture. Consequently, the transfer formulation between the external and internalfeld is obtained. Numerical comparisons are given to demonstrate the validity ofthe method of transfer functions.3. For aperture coupling problems of a single layer rectangular shielding cavityand a two-wire transmission line inside it, the terminal responses are estimated bytwo methods. One is the Agrawal coupling model method of the aperture to trans-mission line coupling based on the transfer functions. Another is the network BLT equation method of the aperture to transmission line coupling based on transmissionline topological networks. Numerical examples are given to demonstrate the valid-ity of the Agrawal coupling model method and that of the network BLT equationmethod.4. For aperture coupling problems of a double layer rectangular shielding cavityand a two-wire transmission line inside the inner cavity, two methods are proposedto compute the terminal responses including the methods of EMT1and EMT2,based on the transmission line topological network. EMT1involves the network BLTequation, the internal coupling feld inside the inner cavity and the Agrawal couplingmodel to compute the terminal responses of the line in the inner cavity. EMT2usesone network BLT equation to calculate the response voltages at one point in theouter cavity and another network BLT equation to compute the terminal responsesof the line inside the inner cavity. Simulation results based on these two methodsare in close agreement.5. Electromagnetic interaction of an empty multiaperture rectangular cavityand that of a muliaperture rectangular cavity and a two-wire transmission line in-side it are investigated. The linear superposition method based on the transferfunctions and the multistep iterative algorithm based on electromagnetic topologyare proposed.更多还原