Three-Dimensional Terahertz Imaging With Sparse Multistatic Line Arrays
Three-Dimensional Terahertz Imaging With Sparse Multistatic Line Arrays
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DOI：
10.1109/jstqe.2017.2673552
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发表时间：
2017-07-01
影响因子：
4.9
通讯作者：
Friederich, Fabian
中科院分区：
文献类型：
--
作者：
Baccouche, Bessem;Agostini, Patrick;Friederich, Fabian
许多已建立的太赫兹成像模式一方面受到分辨率和视场之间权衡的限制，例如在焦平面阵列的情况下，另一方面受到有限的景深的影响，例如在准光学太赫兹成像配置的情况下。此外，典型的扫描解决方案需要耗时的测量程序，并限制了太赫兹成像技术的巨大潜在工业部署。稀疏多基地线阵成像与数字波束形成 (DBF) 技术相结合，使我们能够克服这些限制，并提供物体的三维 (3D) 太赫兹图像重建。该贡献从一般角度解决了此类太赫兹成像系统的设计问题，重点是稀疏线阵列的设计，同时考虑了物体的散射特性。基于该设计理念，讨论了新型高度稀疏3D太赫兹成像系统的实现。该系统的稀疏线阵列在 75 至 110 GHz 的频率范围内运行，并与传送带结合使用以生成合成采样孔径。该系统能够以高达几十厘米/秒的进给运动生成具有数十兆体素的 3D 太赫兹图像。此外，还讨论了在 240 GHz 下运行且具有集成 SiGe 传感器元件的成像系统的稀疏阵列设计。此外，还比较了三种不同的 DBF 算法的计算效率。
Many established terahertz imaging modalities are on one side restricted by the tradeoff between resolution and field of view such as in the case of focal plane arrays and on the other side suffer from a limited depth of field such as in the case of quasi-optical terahertz imaging configurations. Furthermore, typical scanning solutions require time-consuming measurement procedures and restrict significant potential industrial deployments of terahertz imaging technology. Imaging with sparse multistatic line arrays in combination with digital beam forming (DBF) techniques enables us to overcome these limitations and offer three-dimensional (3D) terahertz image reconstructions of the object. This contribution addresses the design of such terahertz imaging systems from a general point of view with the focus on the design of sparse line arrays, while considering objects scattering properties. Based on this design concept, the realization of a novel highly sparse 3D terahertz imaging system is discussed. The sparse line array of the system is operating within a frequency range from 75 to 110 GHz and is used in combination with a conveyor in order to generate a synthetic sampling aperture. The system is capable to generate 3D terahertz images with tens of megavoxels at feed motions of up to a few 10 cm/s. Also, a sparse array design in regard to an imaging system operating at 240 GHz with integrated SiGe sensor elements is discussed. In addition, three different DBF algorithms are compared in regard to their computational efficiency.