基于非均匀超表面的带宽和增益改善型缝隙天线设计

Design of slot antenna with bandwidth and gain improved based on nonuniform metasurface

针对贴片天线普遍存在带宽及增益性能不足的问题,提出了一种通过非均匀超表面实现的带宽和增益改善型天线.首先,采用带有切角的缝隙贴片作为初始天线;然后,为进一步增强辐射特性,围绕初始天线周围排列了方形切角贴片,以此形成非均匀超表面.仿真结果表明,与初始天线相比,额外产生了两个谐振频率,导致反射系数S11带宽范围达到4.4~6.6 GHz.此外,轴比值突破了3 dB线,3 dB轴比带宽范围为4.7~5.7 GHz,增益平均提高了3 dB,峰值增益达到11.3 dBic;在5.05GHz处的辐射方向图表现出低于25 dB的低交叉极化.

In order to solve the problem of insufficient bandwidth and gain performance of patch antenna,this paper presents a kind of antenna with bandwidth and gain improved which is realized by a nonuniform meta-surface.Firstly,slit patches with cut corners are used as the initial antenna.Then,to further enhance the radiation properties,square corner-cut patches are arranged around the initial antenna to form a nonuniform meta-surface.The simulation results are shown as follows:compared with the initial antenna,two additional resonant frequencies are generated,resulting in a reflectance S11 bandwidth range of 4.4-6.6 GHz.Moreover,the axial ratio breaks through the 3 dB line;the 3 dB axial ratio bandwidth ranges from 4.7 GHz to 5.7 GHz;the gain is increased by an average of 3 dB,and the peak gain reaches 11.3 dBic.In addition,the radiation pattern at 5.05 GHz shows a low cross polarization of less than 25 dB.