一种星载平面螺旋天线的小型化设计方法

摘要

A satellite cavity-backed planar spiral antenna miniaturization method is discussed.Through bow tie loading transmission segment and zigzag curve loading radiant and end segments,the low and high frequency properties of the spiral antenna are improved,and its defects,such as long antenna arm,high transmission loss and low efficiency,are overcome,then increasing its effective length.A reasonable design of cavity height increases the gain of antenna.The design parameters of cavity-backed spiral antenna are optimized to achieve wideband,high gain and miniaturization.Prototype antenna measurement results show that it maintains a good circularly polarized radiation in the operation frequency range of 5：1.Compared with the conventional antenna,the antenna geometric size is much smaller than the same band planar spiral antenna.%探讨了某星载背腔式平面螺旋天线的小型化设计方法。通过螺旋线传输段进行蝶形加载;辐射段和截止段进行曲线锯齿加载;改善了螺旋天线的低频和高频特性,克服了传统阿基米德螺旋天线臂长、传输损耗大、效率低的缺点,增加了螺旋曲线的有效长度;通过合理设计天线的反射腔高度,提高了天线的增益。对背腔式平面螺旋天线各参数进行了综合优化设计,研制出了具有小型化、宽频带、高增益等特点的复合加载平面螺旋天线实物样机,并进行了测量,结果表明,所设计的天线在带宽为5∶1工作频带内具有良好的阻抗和圆极化辐射特性,与传统螺旋天线相比,天线的几何尺寸要远小于同频带的平面螺旋天线。