一种宽带分形自互补单极子天线的设计

A Self-Complementary Fractal Monopole Antenna with Broad Bandwidth

提出一种结合分形与自互补理论的新型宽带单极子天线。辐射部分由Sierpinski分形图案的金属贴片和互补的缝隙贴片印刷在FR-4介质板上构成,由微带线经阻抗变换后馈电。分形技术的利用使得该天线实现了20%的尺寸缩减,自互补结构则大大拓展了天线的带宽,两者的结合使得该天线在保持平面结构的同时取得优良的性能。仿真与测试得到该天线在4.98~9.93 GHz频带内反射系数小于-10 dB,具有66.4%的带宽,带内增益在1.3~3.3 dBi之间。该天线具有平面、宽带、小型化的优点,在小型化通信系统中具有良好的应用前景。

A novel broadband monopole antenna is presented based on self-complementary and fractal theories. The radiation structure is composed of a Sierpinski shaped conductor patch and a complementary one with slot, which is fed by a microstrip line through impedance transform parts. The antenna can achieve 20% size reduction due to the fractal technology, while the self-complementary structure can greatly expand the bandwidth. The combination of the two makes the antenna achieve excellent performance while maintaining the planar structure. Simulation and measurement results show that the antenna has 66.43% bandwidth from 4.98 GHz to 9.93 GHz, and the in-band gain varies from 1.3 dBi to 3.3 dBi. The antenna has the advantages of planar structure, broadband and miniaturization, so it has a good application prospect in miniaturized communication systems.