Truncation error mitigation in free-space automotive partial spherical near field measurements
Truncation error mitigation in free-space automotive partial spherical near field measurements
复制标题
自由空间汽车部分球面近场测量中的截断误差缓解
DOI：
10.23919/amtap.2017.8123710
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
L. Foged
中科院分区：
文献类型：
--
作者：
F. Saccardi;F. Rossi;L. Scialacqua;L. Foged
现代汽车中安装的天线通常是高度集成的。在这种情况下，整个车辆都会产生辐射场，特别是在 VHF 等较低频率下。因此，通常需要对整车进行完整的表征。对于低至 70 MHz 的频率，一种被广泛接受且具有成本效益的解决方案是多探头球形近场 (NF) 系统，其中扫描区域在地平线以下被截断，以最大限度地减小系统尺寸。为了模拟下半球适当的自由空间条件，底层覆盖有吸波材料 [1]。如果应用标准近场到远场 (NF/FF) 转换，此类系统的部分 NF 采集会导致截断错误 [2-3]。文献[4-9]描述了通过不同的后处理技术来减轻一般测量场景中的截断误差。在这篇文章中，首次通过汽车场景的实验研究了两种技术的缓解能力。测量是在全球多探头系统中的 1:12 比例车载天线上进行的。缩放后的系统和车辆代表频率范围 70-400 MHz 的实际尺寸系统。进行截断和完整 3D 测量以进行比较。
Antennas installed in modern cars are often highly integrated. In such cases, the entire vehicle is contributing to the radiated field, in particular at lower frequencies such as VHF. The complete characterization of the full vehicle is thus typically required. For frequencies down to 70 MHz, a widely accepted and cost effective solution is a multi-probe spherical Near Field (NF) system in which the scanning area is truncated below the horizon to minimize system dimensions. In order to emulate a proper freespace condition in the lower hemisphere, the ground floor is covered with absorbing material [1]. The partial NF acquisition of such systems leads to truncation errors if standard Near Field to Far Field (NF/FF) transformation is applied [2-3]. The mitigation of truncation error in general measurement scenarios by different post-processing techniques are described in the literature [4-9]. In this contribution, the mitigation capabilities of two techniques are investigated by experiment for an automotive scenario for the first time. The measurements have been performed on a 1:12 scaled vehicle-mounted antenna in a full-sphere multi-probe system. The scaled system and vehicle is representative of a real size system in the frequency range 70–400 MHz. Both truncated and full 3D measurements are performed for comparison.