腔体加载式圆极化波导缝隙天线设计

摘要

Circularly polarized antennas have attracted extensive attention in modern communication systems due to their inherent advantages.In this paper,a circularly polarized antenna constructed by a traditional waveguide slot antenna loaded with rectangular cavi⁃ties is presented.The realization mechanism of the circularly polarized wave radiated by the cavity and the effect of cavity dimensions on the impedance bandwidth of the antenna are also analyzed.The impedance characteristics and the circular polarization characteristics of this type of antenna can be tuned independently.The designed antenna operates in X⁃band and consists of 1×10 unit cells.The measured results show that the right hand circular polarized gain is about 16.5 dB at the center frequency.The axial ratio is less than 1 dB in the direction of main radiation and the impedance bandwidth (VSWR<2) is 64 MHz.The measured data is quite consistent with the simula⁃tion results.%圆极化天线由于其自身具有的众多优点，在现代通信系统中日益受到广泛关注。设计了一种通过在传统波导缝隙天线上加载旋转矩形腔体实现圆极化辐射的天线形式，分析了腔体辐射圆极化波的机理以及腔体对天线阻抗带宽的影响。该天线具有阻抗特性和圆极化特性独立可调的优点。加工实现了一种工作于X频段、具有1×10个单元的天线结构。测试结果表明，在中心频率处右旋圆极化增益约为16�5 dB，主辐射方向上轴比优于1 dB，阻抗带宽（ VSWR＜2）约为64 MHz。测试结果与仿真数据取得了较好的一致性。