一种宽频带圆极化微带天线的设计

The design of Broad Band Circularly Polarizedmicrostrip Antenna

设计了一种宽频带圆极化微带天线。其结构为双层介质与空气层结合,辐射贴片为单个圆形金属片,通过电容耦合馈电的两个圆形金属片与威尔金森功分器相接,功分器的两个端口输出的功率幅度相同,相位相差90°。天线的3dB极化带宽为56%,VSWR<2的驻波比带宽为64%,增益在52%的带宽范围内变化在1dB以内。天线的远场方向图极化特性在35%的带宽范围内较好。

A broad band circularly polarizedmicrostrip antenna is presented in this paper. The structure of antenna is the combination of dual substrate and air, single circularmetal disk as radiate patch. The dual circularmetal disk feed by capacitively coupled contact with the Wilkinson power divider, the power of the two output are equal in amplitude and 90 degree phase shift. The 3dB axial ratio bandwidth as large as 56%, the VSWR 〈2 impedance bandwidth of about 64%, the ldB variation of antenna gain bandwidth of about 52% . The polarized feature of antenna pattern is well in 30% bandwidth.