小型多馈源宽频微带天线分析与设计

Analysis and Design of a Compact Multi-Feed Broadband Microstrip Antenna

本文着重研究了提高轴比带宽的方法。从多馈源实现圆极化的机理出发,从理论上分析证明了采用多馈源技术可有效展宽轴比带宽。在小型微带贴片天线上,设计馈电网络,采用探针馈电,为贴片提供等幅、相位相差90°的激励,形成圆极化。仿真及实测结果表明,这种天线与单馈点天线相比,展宽了轴比带宽,提高了低仰角不圆度指标。

This paper focuses on how to improve the axial ratio bandwidth. Starting from the mechanism of the circular polarization realizing through the multi-point feed, the application of this technology can effectively improve the axial ratio bandwidth theoretically. On the small microstrip antenna, a feed network which provides two excitations in equal amplitudes, 90 degrees in phase offset for the patches to form the circular polarization through two probes was designed. Both simulation and test results illustrated that this kind of microstrip antenna improves the axial ratio bandwidth and circular polarization purity in low elevation compared to the single feed point antenna.