Abstract

This paper proposes a method for measuring the antenna radiation pattern (RP) with ultrashort pulses using the tower method at an open test site. It has been shown by experiments that the far-field boundary does not depend on the pulse duration if the bandwidth of exciting pulse exceeds that of antenna. When measuring in the interference zone, it is possible to separate the direct pulse and the pulse reflected from the underlying surface in time domain at any RP shape of the antennas used. The time window method makes it possible to exclude reflections from the ground and simulate the free space. The energy attenuation typical for the free space has been demonstrated when radiating at raised antennas and using a time window. In this case, there is no interference pattern typical for narrowband signals. It is shown that if the pulse reflected from the ground cannot be eliminated, the attenuation acquires the character of propagation along the underlying terrain. To demonstrate the use of the proposed technique, measurements of the horn antenna RP obtained by the pulse method are presented, and the results obtained are compared with the measurements in an anechoic chamber employing narrowband signals.

中文翻译：

---

使用超短脉冲进行时域天线测量的特点

摘要

本文提出了一种在开放测试现场使用塔法测量超短脉冲天线辐射方向图 (RP) 的方法。实验表明，如果激励脉冲的带宽超过天线的带宽，远场边界不依赖于脉冲持续时间。在干扰区进行测量时，可以在所用天线的任何 RP 形状下在时域中分离直接脉冲和从下垫面反射的脉冲。时间窗方法可以排除地面反射并模拟自由空间。当在凸起天线处辐射并使用时间窗口时，已经证明了自由空间的典型能量衰减。在这种情况下，不存在窄带信号的典型干扰模式。结果表明，如果地面反射的脉冲不能被消除，则衰减具有沿下伏地形传播的特征。为了演示所提出的技术的使用，介绍了通过脉冲方法获得的喇叭天线 RP 的测量结果，并将获得的结果与使用窄带信号的消声室中的测量结果进行了比较。