A new scheme to achieve high resolution in passive millimeter wave imaging (PMMWI) using electromagnetic (EM) vortex beams is proposed in this article. The spatial resolution of the traditional PMMWI system based on the mechanically or electronically controlled scanning scheme is mainly limited by the beam width of the receiver. However, it is not practical to fabricate an antenna that is too large, another possible way to improve the resolution is to increase the sampling points but will increase the imaging time. In this article, the multimode EM vortex beam is applied to achieve high resolution with less sampling points. The imaging scene is first discretized into small grid cells, and then multimode measurements are conducted during the scanning process to construct equations to solve the unknown brightness distribution. The compress sensing method is applied to reduce the number of orbital angular momentum mode. Simulation results demonstrate that high resolution can be achieved by the proposed method.

中文翻译：

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电磁涡旋光束高分辨率被动成像

本文提出了一种使用电磁 (EM) 涡旋光束在无源毫米波成像 (PMMWI) 中实现高分辨率的新方案。基于机械或电子控制扫描方案的传统PMMMI系统的空间分辨率主要受接收器波束宽度的限制。然而，制作太大的天线是不切实际的，另一种提高分辨率的可能方法是增加采样点，但会增加成像时间。在本文中，多模 EM 涡旋光束用于以较少的采样点实现高分辨率。首先将成像场景离散成小的网格单元，然后在扫描过程中进行多模测量，构建方程来求解未知的亮度分布。应用压缩传感方法来减少轨道角动量模式的数量。仿真结果表明，所提出的方法可以实现高分辨率。