In this paper, a comprehensive study of millimeter-wave (mmW) imaging for far-field and near-field objects using 1-bit programmable metasurface (PMS) is presented. Theoretical PMS imaging simulation models are proposed by using plane-wave angular spectrum approach, in which two simulation models based on the flexible mmW beam-forming of PMS are developed. The first imaging model steers the high-gain beams electronically to scan over the region of interest, which is suitable for far-field object detection and surveillance. In the second model, randomly complex beams are generated that can sample the target objects in time domain, which is suitable for Fresnel region imaging. Physical optics theory is employed in the two imaging models for calculating reflected waves. Then, a 1-bit $20\times20$ PMS imager operating at 35 GHz is designed. The PMS imager is composed of a PIN-diode-loaded metasurface and a control board with 400 output channels. Finally, we measure 64 groups of randomly distributed fields using the planar near-field scanning technique in the anechoic chamber. Through imaging reconstruction, it is verified that the proposed PMS is a promising technique for mmW imaging with excellent performance.

中文翻译：

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使用 1 位可编程超表面的毫米波成像：仿真模型、设计和实验

在本文中，提出了使用 1 位可编程超表面 (PMS) 对远场和近场物体进行毫米波 (mmW) 成像的综合研究。利用平面波角谱方法提出了理论PMS成像仿真模型，其中建立了两种基于PMS柔性mmW波束形成的仿真模型。第一个成像模型以电子方式引导高增益光束扫描感兴趣的区域，适用于远场物体检测和监视。在第二个模型中，随机生成复杂光束，可以在时域对目标物体进行采样，适用于菲涅耳区域成像。两种成像模型均采用物理光学理论来计算反射波。然后，设计了一个工作在 35 GHz 的 1 位 $20\times20$ PMS 成像器。PMS 成像器由加载 PIN 二极管的超表面和具有 400 个输出通道的控制板组成。最后，我们在消声室中使用平面近场扫描技术测量了 64 组随机分布的场。通过成像重建，验证了所提出的 PMS 是一种具有优异性能的毫米波成像技术。