带反射腔的分布式电阻加载探地雷达天线设计与分析

摘要

In this study, we investigated the use of a half-ellipse dipole with distributed resistor-loading. By improving the structure of the antenna arms and using distributed resistor-loading technology, the current reflection at the end of dipole is significantly reduced, the input impedance is improved, and the operation bandwidth is widened. We decreased the backward radiation of the antenna with a cubic metal-reflective cavity and also improved the ground penetration ability. The proposed antenna was simulated and designed with electromagnetic computing software; on the basis of the design results, we fabricated the antenna sample. Measurement results of the return loss and radiation characteristics of the proposed antenna confirm the validity of the simulation. We applied the proposed antenna in a GPR system as an underground target detection experiment; on the basis of the experimental results, we conclude that the antenna is able to meet the needs of GPR systems.%该文研究了一种半椭圆结构分布式加载偶极子天线。通过改进天线臂结构以及采用分布式电阻加载，有效降低电流在天线末端的反射，能够改进天线的输入阻抗特性，展宽天线的工作频带。应用长方体金属反射腔，减小了天线的后向辐射，增强了天线的地下穿透能力。利用电磁计算软件对天线进行了仿真和设计，并加工制作了一部样机，测试了样机的反射损耗和辐射特性等性能参数，测试与仿真结果较为贴合。将该天线应用于探地雷达系统进行地下目标探测实验，实验结果证明该天线满足探地雷达系统的需要。