应用于超宽带的小尺寸宽带共面波导馈电分形天线

Small Size Coplanar Waveguide Feed Fractal Antenna for Ultra-Wideband Applications

超宽带技术需要小尺寸、宽带宽和良好全向辐射图的天线,因此提出了一种紧凑型非对称共面波导馈电阶梯状超宽带分形天线。利用H形辐射体、改进馈线结构、非对称馈电和开槽接地板技术实现了4.56 GHz^13.10 GHz的阻抗带宽。在工作频带内所有频率点的H平面上实现了全向辐射方向图。E面方向图在较低频率时是双向的并在较高频率时转变为定向的。此外,针对3种不同的基底材料对所设计天线结构进行了分析。实验结果验证了所设计天线结构的适用性。与其他天线相比,该天线结构的平均增益为2.84dB,尺寸较小且带宽更高。

Ultra-wideband technology requires antenna with small size,wide bandwidth,and good omnidirectional radiation patterns.Therefore,a compact asymmetric coplanar waveguide feed stepped ultra-wideband fractal antenna is proposed.The impedance bandwidth of 4.56 GHz^13.1 GHz is achieved by H-shaped radiator,improved feeder structure,asymmetric feed and slotted ground plate technology.An omnidirectional radiation pattern is implemented on the H plane at all frequency points within the operating band.The E-plane pattern is bidirectional at lower frequencies and becomes directional at higher frequencies.In addition,the designed antenna structure was analyzed for three different base materials.Experimental results verify the applicability of the designed antenna structure.Compared with other antennas,the antenna structure has an average gain of 2.84 dB,a smaller size and a higher bandwidth.