基于分形的宽带漏波天线研究

设计了一种新型的具有宽频带特性的微带平面漏波天线.该天线由基片集成波导喇叭、抛物面结构和一组30×10单元的微带贴片阵列组成.分析比较了普通贴片和分形结构贴片天线的带宽和辐射特性，发现具有分形结构单元的天线具有更宽的频带和更好的辐射特性.仿真结果表明，采用Minkowski准分形结构贴片单元的漏波天线在18～22GHz内回波损耗都大于10dB，带内增益可达17dB.实测结果表明，天线在18～22GHz内回波损耗大于10dB，在20GHz增益为14dB，适合于卫星应用.这为将其用作对地观测卫星数传天线提供了新的理论支撑.该新型微带平面漏波天线具有高增益、宽频带、小体积、轻质量和波束扫描等优势，可作为航天器天线的优选. 

Design and Analysis of a Wide Band Leaky Wave Antenna Based on Fractal

A planar wide band Leaky Wave Antenna (LWA) is proposed in this paper. The antenna is composed of two substrate integrated waveguide horns, the paraboloid structure and a microstrip patch array with 30×10 units. In order to obtain wide bandwidth and high gain, a Minkowski quasi-fractal is properly designed in each unit cell of the patch array. A comparison between two different designs of conventional patch and fractal patch has been done.The simulated results indicate that the LWA with fractal patches has the impedance characteristics with a frequency bandwidth of 18~22GHz for input return loss more than 10dB and a max gain of 17dB at 20GHz. The measured results show that the return loss of 18~22GHz is greater than 10dB and the peak gain at 20GHz is 14dB. The antenna has the advantages of small size, easy integration, high gain, wide band and beam scanning. It can be widely used in data transmission antenna of satellite.