A fully metallic radiating element is presented in this article for single and dual circular polarization applications. The shape of the radiating element corresponds to a bow-tie-shaped field rotator designed to generate two orthogonal modes in quadrature as a basis for circular polarization. The bow-tie-shaped basic element is able to provide low axial ratio with a compact, easy-to-manufacture profile. In addition, it allows diverse ways of operation: feeding through a rectangular waveguide provides single circular polarization, while square waveguide is used for dual circular polarization. The radiating element has been designed at the Ku band and validated by the competitive experimental results. In the case of single circular polarization, over 21% bandwidth has been obtained under 15 dB return loss and 3 dB axial ratio criteria, with a radiating element height of $0.75 {\lambda }_{0}$ (free-space wavelength) at 18 GHz. The dual circularly polarized version achieves 18.3% bandwidth when 15 dB return loss and 3 dB axial ratio are established. In this case, the required antenna height is slightly higher than ${\lambda }_{0}$ at 18 GHz.

中文翻译：

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用于单圆极化和双圆极化的领结形辐射元件

本文介绍了一种用于单圆极化和双圆极化应用的全金属辐射元件。辐射元件的形状对应于蝴蝶结形场旋转器，设计用于生成正交的两个正交模式，作为圆偏振的基础。领结形基本元件能够以紧凑、易于制造的外形提供低轴比。此外，它允许多种操作方式：通过矩形波导馈电提供单圆极化，而方形波导用于双圆极化。辐射元件是在 Ku 波段设计的，并得到了竞争性实验结果的验证。在单圆极化情况下，在15 dB回波损耗和3 dB轴比标准下获得了超过21%的带宽， $0.75 {\lambda }_{0}$ （自由空间波长）在 18 GHz。当建立 15 dB 回波损耗和 3 dB 轴比时，双圆极化版本可实现 18.3% 的带宽。在这种情况下，所需的天线高度略高于 ${\lambda }_{0}$ 在 18 GHz。