In this article, we introduce the tapered impedance half-impulse radiating antenna (TI-HIRA). This innovative version of the HIRA allows the direct connection of COTS, $50~\Omega $ generators to the antenna, without requiring external transformers and without using the large, blocking, plates that would be required in the traditional constant-impedance case. The idea relies on the use of feeders having a characteristic impedance that increases progressively, as a function of the radial distance between the focal point and the parabolic reflector. The additional effort required for manufacturing the new profile is offset by the reduced number of electrical and mechanical parts required for operating the radiating system. Various impedance profiles for the feeders are presented and compared. The design is discussed and validated, both analytically and by full-wave simulations demonstrating that the performances of the original HIRA remain.

中文翻译：

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锥形阻抗半脉冲辐射天线

在本文中，我们介绍了锥形阻抗半脉冲辐射天线（TI-HIRA）。HIRA的这一创新版本可直接连接COTS， $ 50〜\ Omega $ 无需天线变压器，也无需使用传统的恒定阻抗情况下所需的大块隔板。该思想依赖于具有特性阻抗的馈线的使用，该特性阻抗根据焦点和抛物线反射器之间的径向距离而逐渐增加。制造新型材所需的额外工作被减少了操作辐射系统所需的电气和机械零件的数量所抵消。呈现并比较了馈线的各种阻抗曲线。通过分析和全波仿真对设计进行了讨论和验证，证明了原始HIRA的性能仍然存在。