具有三陷波特性的类Sierpinski分形超宽带天线

Sierpinski-like fractal ultra-wideband antenna with triple-band-notched characteristics

为避免窄带通信系统对超宽带(ultra-wideband,UWB)系统的干扰冲突,提出一款具有三陷波特性的类Sierpinski分形UWB天线.辐射贴片采用圆环与五角星形嵌套迭代的2阶类Sierpinski分形结构,并采用缺陷地结构接地板以实现良好的UWB特性.通过在分形结构的上部添加对称倒L形开路枝节,在微带馈线两侧添加对称L形开路枝节,并在馈线处刻蚀倒π形窄缝隙产生了4.5~4.8 GHz、7.2~7.8 GHz和8.0~8.5 GHz三个频段的陷波特性.仿真和实测结果表明,天线在3.1~18.1 GHz的频段内,可有效抑制国际卫星波段、X卫星波段和国际电信联盟波段等窄带系统的干扰.该天线除滤波频段内,在通带频段内有较稳定的增益和全向辐射特性,可用于各种UWB系统中.

In order to avoid the interference conflict of narrow-band communication system to ultra-wideband(UWB)system,a Sierpinski-like fractal UWB antenna with triple-band-notched characteristics is proposed.The radiating patch adopts a second-order Sierpinski-like fractal structure with circular and pentagonal nested iterations,and uses the defective structure ground plate to achieve good ultra-wideband characteristics.By adding symmetrical inverted L-shaped open branches on the upper part of the fractal structure,and adding symmetrical L-shaped open branches on both sides of the microstrip feeder,and etching the invertedπ-shaped narrow slit at the feeder produces notch characteristics of the 4.5–4.8 GHz,7.2–7.8 GHz and 8.0–8.5 GHz bands.The simulation and measured results show that the antenna is effective in suppressing interference from narrow-band systems such as the international satellite frequency band,the X band satellite and the ITU-band in the 3.1–18.1 GHz band.In addition to the filtering frequency band,the antenna has relatively stable gain and omnidirectional radiation characteristics in the passband,and can be used in various ultra-wideband systems.