Multiple-input-multiple-output (MIMO) millimeter-wave (mmWave) sensors for synthetic aperture radar (SAR) and inverse SAR (ISAR) address the fundamental challenges of cost-effectiveness and scalability inherent to near-field imaging. In this paper, near-field MIMO-ISAR mmWave imaging systems are discussed and developed. The rotational ISAR (R-ISAR) regime investigated in this paper requires rotating the target at a constant radial distance from the transceiver and scanning the transceiver along a vertical track. Using a 77GHz mmWave radar, a high resolution three-dimensional (3-D) image can be reconstructed from this two-dimensional scanning taking into account the spherical near-field wavefront. While prior work in literature consists of single-input-single-output circular synthetic aperture radar (SISO-CSAR) algorithms or computationally sluggish MIMO-CSAR image reconstruction algorithms, this paper proposes a novel algorithm for efficient MIMO 3-D holographic imaging and details the design of a MIMO R-ISAR imaging system. The proposed algorithm applies a multistatic-to-monostatic phase compensation to the R-ISAR regime allowing for use of highly efficient monostatic algorithms. We demonstrate the algorithm's performance in real-world imaging scenarios on a prototyped MIMO R-ISAR platform. Our fully integrated system, consisting of a mechanical scanner and efficient imaging algorithm, is capable of pairing the scanning efficiency of the MIMO regime with the computational efficiency of single pixel image reconstruction algorithms.

翻译：多输入多输出（MIMO）毫米波传感器用于合成孔径雷达（SAR）和逆合成孔径雷达（ISAR），解决了近场成像中固有的成本效益和可扩展性这一基本难题。本文讨论并开发了近场MIMO-ISAR毫米波成像系统。本文研究的旋转ISAR（R-ISAR）方案要求目标在距离收发器恒定的径向距离处旋转，同时收发器沿垂直轨道进行扫描。利用77GHz毫米波雷达，考虑球形近场波前，可以从这种二维扫描中重建出高分辨率三维（3-D）图像。尽管现有文献工作包括单输入单输出圆迹合成孔径雷达（SISO-CSAR）算法或计算效率低下的MIMO-CSAR图像重建算法，但本文提出了一种用于高效MIMO 3-D全息成像的新型算法，并详细介绍了MIMO R-ISAR成像系统的设计。所提出的算法对R-ISAR方案应用了多站到单站的相位补偿，从而能够使用高效的单站算法。我们在原型MIMO R-ISAR平台上展示了该算法在真实成像场景中的性能。我们的全集成系统由机械扫描器和高效成像算法组成，能够将MIMO方案的扫描效率与单像素图像重建算法的计算效率相结合。