加载微带贴片的圆极化波导缝隙天线的设计

Design of Circularly Polarized Waveguide Slot Antenna of Microstrip-Appended

摘要: 本文提出了一种波导缝隙天线实现圆极化的新方法。波导上面的宽边上加载一层印刷有微带贴片的介质基片。在波导宽边开并联纵缝，从波导缝隙耦合电磁波至其上方的微带贴片，实现圆极化辐射。对天线单元进行了参数仿真分析，在工作频率为10 GHz处轴比约为0.82 dB，天线的相对轴比带宽(AR £ 3 dB)约为3.2%。并针对其辐射效率较低的问题进一步提出了加载二元微带的改进方案，改进后的天线单元辐射效率明显提高，相对轴比带宽(AR £ 3 dB)约为2.4%。

Abstract: A novel circularly polarized waveguide slot antenna has been proposed in this paper. A substrate layer printed with microstrip patches is loaded on the upper broad wall of the waveguide. Parallel longitudinal slots are cut in the broad wall of waveguide so that the electromagnetic waves couple to the upper microstrip patch to realize circularly polarization. Parametric simulated analysis is conducted for an antenna element. Axial ratio of 0.82 dB is obtained at center frequency 10 GHz and the bandwidth with axial ratio less than 3 dB is 3.2%. To solve the problem of low radiation efficiency of the element, we proposed a two-unit scheme which is helpful to improve the element efficiency. Corresponding band width with axial ratio less than 3 dB is 2.4%.