一种新型的低剖面定向宽带圆极化天线设计  

A novel wideband directional circular polarized antenna with low profile

作　　者：李长江 刘运林[1] 钟选明 LI Changjiang;LIU Yunlin;ZHONG Xuanming(School of Physical Science and Technology,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]西南交通大学物理科学与技术学院,四川成都610031

出　　处：《电子元件与材料》2024年第1期104-109,114,共7页Electronic Components And Materials

基　　金：国家自然科学基金(62271416);超宽带高增益阵列天线研究“国家重点实验室开放课题”。

摘　　要：针对低剖面定向圆极化天线结构复杂、带宽较窄等问题,设计了一款基于类同轴波导的紧凑型宽带定向圆极化天线。该天线于波导上表面印制螺旋缝隙,波导内端口处使用同轴接口馈电。天线端口反射系数性能可通过合理地调节波导内外导体尺寸进行优化,避免了馈电网络的使用,天线结构得到简化。另外,天线无需借助反射地板可直接实现定向辐射性能,使剖面尺寸降低至0.1λ(λ为自由空间中最低频点波长),并由于同轴波导的宽带通性实现57%(2.7~4.85 GHz)的有效带宽。运用介质集成波导技术制作该结构天线,并进行仿真和测试,两者结果吻合良好,证明此种设计方法的有效性。与其他定向圆极化天线相比,该天线整体结构紧凑、设计简单、避免了复杂的馈电网络,且具有较宽的有效带宽。In order to solve the problems of complex structure and narrow bandwidth of low-profile directional circular polarized antennas,a novel compact directional broadband circular polarized antenna base on the coaxial-like waveguide was proposed.A spiral slot was formed on the upper surface of the coaxial-like waveguide,and the coaxial interface was used for feeding at the inner port of the waveguide.The size of the inner and outer conductors could be adjusted to optimize the antenna reflection coefficient performance with no need of an external balun,and therefore the antenna structure was simplified.In addition,the antenna directional radiation performance could be directly achieved without the ground plane,and the profile was reduced to 0.1λ(λis the free space wavelength at the lowest frequency).And due to the wide bandpass of the coaxial waveguides,the wide bandwidth of 57%(2.7-4.85 GHz)was achieved.The antenna prototype was fabricated by dielectric integrated waveguide technology and measured to verify the design.Good agreement between the simulation and measurement results was obtained,showing the validity of this design method.Compared with other directional circular polarized antennas,this antenna has compact structure and simple design,avoiding the use of complex feed network,and has a wide bandwidth.

关 键 词：圆极化天线 螺旋缝隙 定向辐射 介质集成波导 

分 类 号：TN821.8[电子电信—信息与通信工程]