卫星导航终端的小型化方形四臂缝隙螺旋天线

Miniaturized Square Quadrifilar Slot Helix Antenna for Satellite Navigation Terminal

设计了一种卫星导航终端的小型化四臂缝隙螺旋天线。天线为方形柱状结构,四条缝隙螺旋臂印制在介质基板外表面,馈电网络印制于介质基板内表面进行耦合馈电;馈电网络为弯折的微带线结构,并延伸至天线底部实现同轴馈电。天线尺寸为23.6 mm×23.6 mm×53.0 mm,实测结果表明,|S11|≤-10 dB的阻抗带宽为7.63%(1.512~1.632 GHz),轴比≤3 dB的圆极化带宽为3.35%(1.556~1.609 GHz),在北斗B1频段中心频率(1.561 GHz)和GPS L1频段中心频率(1.575 GHz)处增益分别达到4.31 dBi和4.84 dBi。该天线采用缝隙螺旋结构,并通过简易的馈电网络耦合馈电实现螺旋天线的圆极化,结构小巧简单,适合批量生产,可应用于卫星导航系统终端设备。

In this paper,a miniaturized quadrifilar slot helix antenna for satellite navigation terminal is proposed.The antenna is a square structure.Four slot helical arms are printed on the outer surface of the medium,while the feeding network is printed on the inner surface of the medium for coupling feeding.The feeding network is a folded microstrip line structure and extends to the bottom of the antenna for coaxial feeding.The Antenna size is 23.6 mm×23.6 mm×53.0 mm.The measured results demonstrate that the impedance bandwidth for|S11|≤-10 dB reaches 7.63%(1.512-1.632 GHz)and circular polarization bandwidth for axial-ratio≤3 dB reaches 3.35%(1.556-1.609 GHz).The gain at the frequency of Beidou B1(1.561 GHz)and GPS L1(1.575 GHz)are 4.31 dBi and 4.84 dBi respectively.The antenna adopts a slot helix structure and realizes circular polarization of the helix antenna by coupling feeding through a simple feeding network.The antenna has small size which is suitable for mass production,and is suitable for use in satellite navigation system terminal equipment.