一种具有宽角稳定相位中心的双频段圆极化GNSS天线设计

本文介绍了一种在宽波束范围内具有稳定相位中心的双频段圆极化 GNSS(全球卫星导航系统)天线。天线设计为层叠空气腔式天线结构，采用幅度相等，相位相差 90°的四端口馈电方式，空气腔式天线在宽角范围内获得了较好的圆极化辐射特性。对称结构以及等幅等相差馈电的天线设计，可在宽角范围内获得较高的相位中心稳定度。测试结果表明:在四个导航频段内， 天线波束宽度大于±36°，±46°角域范围内的轴比小于 3dB，±70°角域范围内的相位中心稳定度小于 1.61mm，具备很强的工程应用价值。

Dual-Band Circular Polarized GNSS Antenna With Stable Phase Center in Wide Angle

A dual-bands circularly polarized GNSS (Global Satellite Navigation System) antenna with stable phase center in wide angle is proposed in this paper. The antenna employs a stacked air-box structure, four ports with equal amplitudes is used for antenna excitation with 90° phase difference successively, in order to achieve good circularly polarized radiation. By using a symmetry structure and feeding by two four points, which are equal in amplitude and equally spaced in phase, high phase center stability can be obtained in a broad angular domain. The model of the antenna is simulated, and a prototype is fabricated and measured. The measured results in GPS L1, L2 band & BD B1, B2 band show that the antenna beam width is greater than ±36°, and at the same time the stability of the antenna phase center is up to 1.61 mm at the domain range angle -70°~70°, and 3dB axial ratio angles are more than -46°~46°,which indicate that the antenna has great engineering application value.