超宽带平面正弦天线的研究与设计.pdf

南京航空航天大学
硕士学位论文
超宽带平面正弦天线的研究与设计
姓名:陈振华
申请学位级别:硕士
专业:电磁场与微波技术
指导教师:曹群生
20090101
南京航空航天大学硕士学位论文
摘要
本文对超宽带平面正弦天线的设计理论及实现方法进行了研究。研究内容主要分为三部分:
1、研制了 3~15GHz 的常规两臂平面正弦天线;2、研制了 3~15GHz 的带有小型化馈电巴伦
的两臂平面正弦天线;3、研制了 3~15GHz 的四臂平面正弦天线。
传统的平面螺旋天线,如阿基米德螺旋天线和等角螺旋天线存在极化方式单一的不足之处,
而正弦天线除了具有传统平面螺旋天线所具有的超宽带、圆极化、单孔径的优点外,还具有独
特的“全极化”特性。本文在超宽带理论和大量仿真计算的基础上,分析了正弦天线结构、介
电常数等参数的变化对天线性能的具体影响,在此基础上设计制造了三款正弦天线实物样机,
并在微波暗室进行了实验测试。
首先设计了工作频段为 3~15GHz 的两臂平面正弦天线,为了实现天线的输入阻抗与 50Ω
同轴电缆的良好匹配,设计了用于该天线平衡馈电的指数渐变微带巴伦。为了弥补该巴伦纵向
尺寸过大的缺陷,设计了“小型化”的微带巴伦,并用于两臂正弦天线的馈电,在保持原天线
电特性的基础上,显著降低了整个天线系统的纵向几何尺寸。同时,为实现正弦天线的“全极
化”特性,设计了带双巴伦馈电结构的四臂正弦天线。上述三款天线均进行了实物样机的研制,
并对其进行了测试,结果表明天线和巴伦在工作频段内较好地符合了设计预期,能够满足工程
应用要求。


关键词:正弦天线,超宽带,全极化,巴伦,小型化
I
超宽带平面正弦天线的研究与设计
Abstract
In the thesis, ultra-wideband (UWB) planar sinuous spiral antenna have been studied and
designed. The mainly works are divided into three parts, namely, a normal two-arm sinuous antenna
at 3~15GHz is made as the first part, then a two-arm sinuous antenna with miniature balun at 3~
15GHz is developed in the second part, finally, a kind of four-arm sinuous antenna is studied as the
last part.
For the traditional planar spiral antennas, such as the Archimedean spiral antenna and
equiangular spiral antenna, their polarization is unique. Besides the characteristics of ultra-wideband,
circular polarization, single-aperture, the sinuous antenna has it’s unique property:omni polarization.
On the basis of the ultra-wideband theory and a large number of simulation experiments, it has been
analyzed the effects of the structure of the sinuous antenna and its permittivity to the antenna
performance. Three kinds of sinuous antennas are fabricated and measured.
A planar two-arm sinuous antenna fed by 50 ohm coaxial-cable is designed as a first kind one for
3~15GHz operation. In order to match the balance structure and the input impedance of the sinuous
antenna, its balun is microstrip line-parallel w