应用于三频GPS的宽频带单馈电天线设计

摘要

为了实现全球定位系统GPS(Global Positioning System)天线小型化并提高其性能,提出了一种新型的三频段GPS宽频带单馈电背腔天线,可在1176.45 MHz(L5)、1227.60 MHz(L2)和1575.42 MHz(L1)3个GPS频段下工作.通过在一端馈送交叉型行波天线并在另一端添加负载,来实现提出天线的右旋圆极化RHCP(Right-Hand Circular Polarization),且配有弯折线辐射器.天线尺寸仅为120 mm×120 mm×29 mm.仿真和实际测量结果显示,提出的单馈电天线无需使用复杂的馈电网络或双馈结构便可提供宽阻抗带宽(VSWR<2)、低轴比(AR)(<2 dB)和高RHCP增益(>4 dBic).%In order to realize the miniaturization of the global positioning system ( GPS ) antenna and improve its performance,a new three band GPS wide band single feed-back cavity antenna is proposed,which can work at three GPS bands such as 1176.45 MHz(L5),1227.60 MHz(L2)and 1575.42 MHz(L1). The right-hand circular polariza-tion(RHCP)of the proposed antenna is made by feeding a crossed type traveling wave antenna at one end and adding a load at the other end,and is equipped with a bend line radiator. The antenna size is only 120 mm×120 mm×29 mm. Simulation and measurement results show that the proposed single feed antenna without the use of complex feed network or double fed structure can provide a wide impedance bandwidth(VSWR<2),low axial ratio(AR)(<2 dB) and high gain RHCP(>4 dBic).