阻容加载偶极天线的宽带性能及效率分析

Analysis of wide-band properties and efficiency for dipole antennas with resistive and capacitive loadings

从工程应用出发 ,提出同时具有分布电阻、集中电容以及同时具有集中电阻、电容这两种加载偶极天线理论分析模型。推导了对应的电流积分方程 ,并用分段正弦伽略金方法进行数值计算。给出了天线电流分布、输入阻抗、方向图及效率的计算结果 ,并与纯分布电阻加载天线进行了比较。分析表明 ,所讨论两种模式阻容加载天线的效率较分布电阻加载天线高 ,但其宽带性下降了。

Two kinds of loaded dipoles are theoretically discussed for purpose of considering bandwidth and efficiency comprehensively. One is the dipole with distributed resistive and concentrated capacitate loading, the other is the dipole with concentrated resistive and capacitate loading. First of all, corresponded current integral equations of two kind theoretical models were given, then numerical calculation were applied by means of Galerkin's method. We derived matrix equation and gave the formula of impedance matrix and voltage matrix. The effect of resistive and capacitate loading were expressed in electric and magnetic matrix respectively. Finally ,current distribution、input impedance 、patterns and efficiencies of two models are given and compared with dipoles with only resistive loading. The result indicates that, the efficiencies of the two loaded antennas are greater than dipoles with only resistive loading, but the wide band properties are deteriorated.