应用于GNSS终端的宽带扁平状双频圆极化微带天线

Wide-Band Flat Dual-Band Circularly Polarized Microstrip Antenna for GNSS Applications

研究一种应用于GNSS终端的宽带扁平状双频圆极化微带天线。通过在天线辐射单元基板外围设置短路加载振子,不仅可以降低天线谐振频率实现天线的小型化设计,而且可有效提升天线辐射增益和工作带宽。双频天线单元分别采用四馈点馈电方式,使得天线拥有稳定且可靠的相位中心偏差值和良好的圆极化特性。针对该天线设计模型,使用仿真软件对天线进行仿真,可以得出天线在高频段(1.166~1.279 GHz)和低频段(1.525~1.607 GHz)内的各项指标表现较优。通过制作实物样机进行实际测量,结果表明该天线在上述高低频双频段范围内辐射增益均大于1.9 dBi,对应高低频段内中心频点的辐射增益大于4 dBi,高频和低频天线3 dB轴比波束带宽分别约为200°和180°。因此,该天线能够较好满足目前GNSS多系统精准定位和测量的应用需求。

This paper researches a flat dual-frequency circularly polarized microstrip antenna for high-precision global navigation satellite system(GNSS)applications.By adding shorting loads on the periphery of the antenna substrate,not only the antenna resonant frequency can be reduced to realize the miniaturization of the antenna,but also the antenna radiation gain and operating bandwidth can be effectively improved.In this paper,the dualfrequency antenna adopts a four-point feeding method,so that the antenna has a stable and reliable phase center offset and excellent circularly polarization characteristics.Aiming at the proposed antenna model,and by using simulation software to simulate the antenna,it can be concluded that the antenna performs better in the high frequency band(1.166~1.279 GHz)and low frequency band(1.525~1.607 GHz).The measured results show that the antenna's gain is greater than 1.9 dBi in both high and low frequency range,and the maximum gain at the high and low frequency band are greater than 4 dBi,respectively.The 3 dB axial ratio beam bandwidth at the high frequency and low frequency are 200°and 180°.Therefore,the antenna can meet the requirements of current GNSS multi-system high-precision positioning and measurement application.