In this letter, an algorithm for synthetic aperture radar imaging of electrically small targets embedded in multilayered cylindrical geometries (e.g., pipes) using nonuniform measurement points is presented. In contrast to previous approaches, this algorithm is able to efficiently handle nonuniform points without exhibiting relevant side lobes in the image. For these purposes, the approach exploits a flexible time-reversal (TR) algorithm enhanced by compressed sensing (CS). The theoretical performance of the algorithm is studied in terms of the point spread function and several images are presented using synthetic full-wave data from CST Microwave Studio. In addition, the approach is empirically validated by performing microwave imaging of a polyvinyl chloride pipe. The results demonstrated that the TR-CS algorithm provides an effective focusing technique for dense nonuniform measurement points, as well as for sparse nonuniform measurement points.

中文翻译：

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基于非均匀测量的多层圆形介质结构SAR成像时间反演压缩感知算法


在这封信中，提出了一种使用非均匀测量点对嵌入多层圆柱形几何结构（例如管道）中的电小目标进行合成孔径雷达成像的算法。与以前的方法相比，该算法能够有效地处理非均匀点，而不会在图像中表现出相关的旁瓣。出于这些目的，该方法利用了通过压缩感知 (CS) 增强的灵活时间反转 (TR) 算法。该算法的理论性能根据点扩散函数进行了研究，并使用 CST Microwave Studio 的合成全波数据呈现了几幅图像。此外，通过对聚氯乙烯管进行微波成像，该方法得到了经验验证。结果表明，TR-CS 算法为密集的非均匀测量点以及稀疏的非均匀测量点提供了有效的聚焦技术。