一种宽带圆极化环形天线  

A broadband circularly polarized ring antenna

作　　者：朱熙铖 陶正壮 肖凌峰 ZHU Xicheng;TAO Zhengzhuang;XIAO Lingfeng(Institute of Radar Technology,College of Electronic&Information Engineering,Nanjing University of Information Science&Technology,Nanjing 210044,China)

机构地区：[1]南京信息工程大学电子与信息工程学院雷达技术研究所,江苏南京210044

出　　处：《电子元件与材料》2022年第11期1215-1221,共7页Electronic Components And Materials

基　　金：国家自然科学基金(61701249);江苏省自然科学基金(BK20160959)。

摘　　要：提出了一款中心频率为4 GHz的单馈宽带圆极化微带阵列天线。单元天线是一种基于环天线的矩形开环微带天线,通过在环天线上引入缝隙使得环天线的平行辐射边缘上具有近似幅值和约90°相位差的电流分布,从而辐射圆极化波。馈电网络采用双面平行带线(Double-Sided Parallel Strip Line, DSPSL)结构和渐变式阻抗变换器实现等功分宽带阻抗匹配。为了实现天线定向辐射,在介质基板正下方约四分之一波长处放置了一个金属反射板。最终加工制作了天线实物,并在微波暗室内进行了相关性能测试。测试结果表明:阵列天线的相对阻抗带宽达到27.5%(3.41~4.51 GHz),3 dB轴比带宽为22.8%(3.6~4.51 GHz)。该阵列天线展现了良好的方向性以及低副瓣特性,其中天线增益最高为13 dBi。A single-fed broadband circularly polarized microstrip array antenna was designed and validated with the central frequency at 4 GHz.A rectangular open-loop antenna was adopted as the antenna element.Current distribution with nearly the same amplitude and 90°phase difference was excited in the rectangular open-loop antenna.Thus,the circularly-polarized radiation can be achieved by the antenna element.In addition,a feed network based on the double-sided parallel strip line(DSPSL)technology was adopted to achieve broadband equal power distribution and impedance matching.Finally,a 2×2 array antenna was designed to achieve high-gain radiation performance.To further improve the antenna radiation directionality,a metal reflector was placed under the radiating antenna with a distance of about a quarter wavelength of the central frequency wave.At last,the proposed array antenna was fabricated and measured.The measured results show that the impedance bandwidth of the array antenna is around 27.5%(3.41-4.51 GHz),and the 3 dB axial-ratio bandwidth is around 22.8%(3.6-4.51 GHz).The array antenna exhibits good radiation directivity and low side lobes characteristics,with the maximum measured antenna gain reaching up to 13 dBi.

关 键 词：环形天线 宽带 圆极化 高增益 单馈 

分 类 号：TN823.15[电子电信—信息与通信工程]