一种宽带圆极化数字型缝隙天线的设计

Design of a Broad Band Circularly Polarized Digital Form Slot Antenna

本文设计了一种新型的微带共面波导馈电的圆极化平面缝隙天线。此天线由宽的数字"0"型缝隙、共面波导馈线和微带馈电网络组成,前两者都是在介质板上表面的金属上开缝完成,后者则在介质板的另一面布线完成。通过合理的设计微带馈电网络给共面波导馈电,可以在其上产生一个奇数模和一个偶数模,同时完成两个模式的90°相位差。通过此微带与共面波导之间的转换电路给缝隙天线馈电从而实现宽带圆极化天线。详细研究了圆极化天线的机理和各个参数对它的影响。通过仿真验证3dB轴比带宽可以达到29%,-10dB反射系数带宽为53%。

A novel broadband circularly polarized planar slot antenna with microstrip to coplanar waveguide(CPW) fed is proposed in this paper.It consists of a wide digit "0" slot and a CPW feedline, both etched on the upper plane of a dielectric substrate, as well as a microstrip to CPW transition on the reverse plane of the substrate. The microstrip-CPW feed structure is appropriately designed so that the even modes and odd modes of the CPW are excited with 90°phase difference,and are then fed to the slot antenna to realize wideband circular polarization.In this paper the mechanism of circular polarization is explained and the influence of the parametric to the antenna is carried out.The simulation 3-dB axial-ratio bandwidth is 29%,and-10 dB reflection coefficient bandwidth is 53%.