一种新型的超宽带平面单极子天线研究

Research on a novel ultra-wide band planar monopole antenna

设计了一种新型的超宽带平面单极子天线。该天线在覆铜介质基板上通过酸蚀制得,介质基板尺寸为30.0 mm×35.0 mm×1.6 mm,材料是相对介电常数为4.4的FR4,该天线通过在辐射元两端底部形成阻抗阶梯形结构和在接地面采用分形技术来达到展宽带宽的目的。利用仿真软件HFSS对天线参数进行仿真和优化。结果表明,该天线频带宽度达到3.0-13.1 GHz（S11≤–10 dB）,相对带宽达125%,达到超宽带天线的范围（3.1-10.6 GHz）。该设计天线在工作频段内具有很好的辐射方向性和增益,满足超宽带通信的需求。

A novel ultra-wide band planar monopole antenna was designed. The antenna was etched on a copper-cladding substrate, whose material was FR4 with relative permittivity of 4.4, and the magnitude was 30.0 mm× 35.0 mm× 1.6 mm. The technique that the lower end of the patch was cut on both sides to generate impedance steps structure and fractal slots in the ground plane was adopted to improve the bandwidth of the antenna. The parameters of the antenna were simulated and optimized with HFSS. The results show that the bandwidth （S11≤-10 dB） is from 3.0 GHz to 13.1 GHz which provides 125% of relative bandwidth, closed to UWB specification（3.1-10.6 GHz）. The antenna has omni directional radiation characteristics and moderate gain throughout its operating band and can be considered as a good candidate for UWB communications.