A microwave measurement system for metallic object detection using swept-frequency radar
A microwave measurement system for metallic object detection using swept-frequency radar
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DOI：
10.1117/12.801671
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发表时间：
2008-10
期刊：
影响因子：
--
通讯作者：
Yong Li;G. Tian;N. Bowring;N. Rezgui
中科院分区：
文献类型：
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作者：
Yong Li;G. Tian;N. Bowring;N. Rezgui
枪支和刀具已经成为公共安全的重大威胁。近年来，基于电磁学（EM）的各种技术已被用于它们的检测。例如，在机场使用了金属探测仪；x射线和太赫兹探测系统已用于行李检查。不同的电磁频率对金属目标的探测表现出不同的优点。本文报道了一种1- 14ghz扫描频率雷达系统，用于金属目标的反射探测。测试和分析了若干金属物体在位置、物体形状、旋转和多物体方面的扫频响应和谐振频率行为。该系统工作频率为1至14 GHz，可实现对距离超过1米的金属物品的传感。通过一系列的实验研究可以发现，由功率谱剖面的傅里叶变换得到的光学深度与金属物体的相对位置密切相关。相干极化和交叉极化射频回波之间的相互关系可以用来区分不同的目标。因此，光学深度和相互关系可以作为有用的特征，用于金属目标的探测和表征，在这部分微波频谱。
Guns and knives have become a significant threat to public safety. Recently, a variety of techniques based on Electromagnetics (EM) have been used for their detection. For example, walk-through metal detection has been used in airports; X-ray and THz detection systems have been used for luggage screening. Different EM frequencies for metallic object detection have demonstrated different merits. This paper reports on a 1-14 GHz swept-frequency radar system for metallic object detection using reflection configuration. The swept frequency response and resonant frequency behaviour of a number of metallic objects, in terms of position, object shape, rotation and multiple objects have been tested and analysed. The system working from 1 to 14 GHz has been set up to implement sensing of metal items at a standoff distance of more than 1 meter. Through a series of experimental investigations, it can be found that the optical depths derived from the Fourier Transform of the power spectrum profile is in close relation with the relative location of the metallic object. The cross correlation between coherence-polarisation and cross-polarisation RF returns can be used to distinguish different objects. Therefore the optical depth and the cross correlation can be used as useful features for metallic object detection and characterisation in this portion of the microwave frequency spectrum.