基于矩量法的线天线电磁散射和电磁辐射分析

针对线电流模型分析半径/波长较大的线天线的缺点,首先利用解析法描述线天线的结构,将线天线模拟为细带模型,线面连接问题转化为面面连接问题,选取RWG函数对天线模型进行剖分,采用矩量法分析不同半径下偶极子天线的电流分布,辐射场,方向图,对散射模式和辐射模式的情况进行了比较。随后计算了有限平板上10m单极子天线的天线特性。计算结果表明,当半径/波长较小时,电流基本沿天线轴向流动,线电流模型适用于分析线天线的问题,半径/波长较大时,横向电流不可忽略,线电流模型不适用于分析线天线的问题。

Analysis on the Electromagnetic Scattering and Radiation of Wire Antenna by Moment Method

Analytical method was chosen to describe the structure of wire antenna.The wire antenna was modeled as a thin strip,wire-surface junction problem was transformed to surface-surface junction problem.RWG function was chosen to discretize the surface of antenna.Current distribution,radiation field and directivity of different radius dipole antennas were analyzed by using method of moment,and then the results of radiation pattern and scattering pattern were compared.The characteristics of 10m monopole antenna on the finite plate were calculated.The results show that： when the radius and or wavelength are small,the current flows along the antenna axial,the line current model is applicable to the problems of wire antennas,but when they are large,horizontal currents cannot be ignored,the line current model is unsuitable for the analysis of wire antenna problems.