背射馈源卡氏天线  

Backfire feed Cassegrain antenna

作　　者：沈真祥[1] 钦耀坤[1] 

机构地区：[1]信息产业部电子第二十三研究所,上海200437

出　　处：《光纤与电缆及其应用技术》2002年第1期29-31,41,共4页Optical Fiber & Electric Cable and Their Applications

摘　　要：背射馈源卡氏天线将背射原理和聚焦原理综合于同一个天线系统之中 ,这就使小口径天线 (与天线波长比 )具有大型卡氏天线的电性能。现介绍的背射馈源卡氏天线其口径为 11.7λ,工作于 Ka波段 ,通过组合馈源的偏置实现了 - 3d B波束交叉的圆锥扫描。天线效率达 4 0 % ,最大旁瓣电平≤ - 19d B,半功率波束宽度为 5 .8°,E面和H面的辐射对称性良好。该天线的独特之处在于慢波结构采用介质敷层金属杆 ,从而提高了结构的工程可靠性和天线的动态稳定性 。By combining backfire principle and focusing mechanism in a single antenna system the backfire feed Cassegrain antenna makes a sm all aperture antenna having the electrical performance of a large Cassegrain antenna. The present backfire Cassegrain antenna has an aperture of 11.7λ and operates at Ka- band.The antenna can be used in conical scan with - 3d B of cross over.For DM=10 .7λ,efficiency=0 .4 0 ,and bandwidth 2θ- 3d B=5 .8°,sidelobe SLM≤ - 19d B can be obtained,and the radiation symm etry of E plane with H plane is good.The antenna features em ploying m etal rod coated with a thin polyethylene layer as the slow-wave structure,thereby im proving the relia- bility of the structure and the dynamic stability of the antenna.Thus the antenna can be used in severe operation conditions.

关 键 词：背射 馈源 卡氏天线 扫描体制 

分 类 号：TN823.28[电子电信—信息与通信工程]