摘要
提出了一种分析金属有耗和表面粗糙对波导传输特性影响的频域有限差分方法(FDFD).该方法按照Maxwell方程组的旋度方程对波导横截面内部场分量进行差分展开,对波导的有耗金属边界和表面粗糙边界分别采用表面阻抗边界条件(SIBC)和等效SIBC代替.将波导内部节点场分量及边界节点场分量满足的方程联立形成特征矩阵方程组,通过求解特征矩阵的特征值可得到指定频率下金属波导的传播常数.和微扰法相比,FDFD方法能分析截止频率以下及形状不规则时表面粗糙有耗波导的传输特性.数值仿真结果表明,随着粗糙度的增大,金属衰减损耗逐渐增大到表面光滑时损耗的2倍.
A finite difference frequency domain method （FDFD） is presented to analyze the propagation characteristics of waveguides with imperfect conductor and rough surface. Two curl equations in the Maxwell system are discretized with difference method in the cross-section of the waveguide, and the loss surfaces and rough surfaces of the waveguide are replaced by the surface impedance boundary conditions （SIBC） and the equivalent SIBC, respectively. Then the eigen equations about the electromagnetic field components are formed and solved to obtain the propagation constants for a given frequency. Comparison with the perturbation method shows that the presented method is effective when the interested frequency is under cutoff frequency and the waveguide has irregular boundary. The simulation results show that with the increase of roughness, the attenuation constant is gradually increased to 2 times of that with smooth surfaces.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2009年第10期85-88,共4页
Journal of Xi'an Jiaotong University
基金
电子测试技术国家重点实验室基础研(61349)
关键词
频域有限差分
传播常数
粗糙表面
等效表面阻抗边界条件
finite difference frequency domain
propagation constant
rough surface
equivalent surface impedance boundary condition
