一种多极化天线的设计

Design of a Multi-polarization Antenna

为了增强信道容量和提高极化信息利用能力,文章设计了一种多极化天线。首先,基于口径耦合馈电技术,优化设计了一种改进的H形线极化缝隙耦合天线;其次,在馈电层设计了单馈线和3dB分支线耦合器作为多极化天线的馈电电路;最后,通过不断优化设计,构建了多层缝隙耦合多极化天线,天线的线极化激励端口采用单馈线形式,左旋/右旋圆极化特性由3dB分支线耦合器来实现。对设计的多极化天线进行了制作和测试,测试结果表明,整个多极化天线的阻抗带宽为12. 8%,线极化与圆极化端口之间的隔离度大于15. 8dB,圆极化端口之间的隔离度在大部分频段内大于15dB,匹配和辐射特性良好。天线具备线极化、左旋圆极化和右旋圆极化3个极化特征,在雷达和通信领域具有一定的应用前景。

In order to enhance signal capacity and improve the utilization of polarization information,a multi-polarization antenna is proposed in this paper.Firstly,based on the aperture-coupled feed technology,the modified H-shape linear polarization slot-coupled antenna is under optimum design.Then,the single feed line and the 3dB branch line coupler are designed as the feed circuit.Lastly,the multi-polarization antenna is constructed through continuous optimum design.The single feed line port is adopted as the linear polarization excitation port.The left-hand and right-hand circular polarization characteristics are realized by the 3dB branch line coupler.The antenna is fabricated and measured.The measured results have demonstrated that the impedance bandwidth can be up to 12.8%.The isolation between the linear polarization port and circular polarization ports is better than 15.8dB while the isolation between circular polarization ports is greater than 15dB during the major frequency band.Meanwhile,the antenna exhibits excellent match and radiation characteristics during the operated frequency band.The antenna considered here is provided with linear polarization,left-hand circular polarization and right-hand circular polarization,which can be found application in radar and communication systems.