一种正六边形嵌套分形超宽带天线的设计

针对当前超宽带天线存在的方向性差、增益小的现状,提出了一种正六边形嵌套分形的超宽带天线。天线利用嵌套分形结构的自相似性和空间填充特性,有效拓展带宽,缩减天线尺寸。通过对天线维数进行仿真分析,选择带宽满足超宽带指标的四维和五维天线;对四维天线和五维天线的E-H面方向图及增益进行对比得知,五维天线较高增益由方向图畸变产生,故选择方向性更好的四维天线为此次设计的目标天线。目标天线尺寸仅为20 mm×23 mm×1.6 mm,带宽为2.7~10.6 GHz,增益为1.8~7.8 dBi,且天线实现了良好阻抗匹配。与引文其它天线相比,目标天线具有较小的尺寸,同时具有良好的方向性和较高的增益。天线实测结果与仿真基本吻合,验证了其研究与应用价值。

Design of An Ultra-Wideband Antenna with A Hexagonal Nested Fractal Structure

Aiming at the current situation that the ultra-wideband antenna has poor directivity and small gain, an UWB antenna with a hexagonal nested fractal structure is proposed. The antenna utilizes the self-similarity and spatial filling characteristics of the nested fractal structure to effectively expand the bandwidth and reduce the antenna size. By simulating and analyzing the antenna dimension, the 4D and 5D antennas whose bandwidth meets the UWB index are selected. Comparing the E-H plane pattern and gain of the 4D and 5D antenna, it shows that the 5D antenna obtains a higher gain by generating distortion. Therefore, the 4D antenna with better directivity is selected as the target antenna. The target antenna size is only 20mm×23mm×1.6mm, the bandwidth is 2.7 -10.6GHz, the gain is 1.8 -7.8dBi, and a good impedance matching is achieved. Compared to other antennas of the citation, the target antenna has a smaller size with good directivity and higher gain. The measured results of the antenna are basically consistent with the simulation results, which verify its research and application value.