ABSTRACT

In this article, the design and development of a novel twin conjugate matched feed horn at Ku-band is presented. This type of multimode feed cancels the undesired high cross-polar components generated because of offset reflector geometry having lower f/D and higher offset angle. Three symmetrically located axial arrays of radial posts are used in the circular waveguide for the generation of TE₂₁ mode along with the dominant TE₁₁ mode. The design and development of a Ku-band twin conjugate feed horns were carried out. The measured return loss of both the feed horns are better than 22 dB, and there is an excellent agreement of measured and simulated radiation pattern of the feed. The simulated cross-polar bandwidth is 5% for better than 10 dB improvement in cross-polarization for an offset parabolic reflector antenna having f/D = 0.5 and offset angle = 90°. In this work, it has been established that the conjugation operation as reported in single feed is maintained in spite of aperture sharing of the twin feed horns.

摘要

在本文中，介绍了在Ku频段的新型双共轭匹配进料喇叭的设计和开发。这种类型的多模馈电消除了由于具有较低f / D和较高偏移角的偏移反射器几何形状而产生的不希望的高交叉极性分量。在圆形波导中使用三个对称定位的径向柱轴向阵列，以生成TE ₂₁模式以及主要的TE ₁₁模式。进行了Ku波段双共轭馈电喇叭的设计和开发。测得的两个馈电喇叭的回波损耗均优于22 dB，并且在测量和模拟馈电的辐射方向图方面有很好的一致性。对于f / D = 0.5和偏置角= 90°的偏置抛物面反射天线，仿真的交叉极化带宽为5％，以实现优于10 dB的交叉极化改善。在这项工作中，已经确定，尽管双进料牛角共用孔，但仍能保持单进料中所报道的结合操作。