This study proposes a method for synthesizing 3-D microwave images using a multiple-input–multiple-output (MIMO) radar. Recent studies on MIMO radar technology have reported promising hardware that can be used in radar imaging. In particular, the increased amount of data acquired from MIMO radar is effective for 3-D radar imaging. Despite the demand for using 3-D radar imaging, the underlying technical challenges have not been addressed. Although the array synthetic aperture radar method is promising, realizing a multichannel radar with numerous channels requires significant effort in terms of hardware. Therefore, an MIMO radar can be used to effectively increase the number of channels with reduced hardware. Studies on beat frequency division (BFD) frequency-modulated continuous wave (FMCW) radars show that the simultaneously transmitted MIMO signal is suitable for radar imaging applications without hindering the along-track imaging performances. In this study, the signal of a BFD FMCW radar mounted on a movable platform is modeled according to the imaging geometry, and a fast Fourier transform-based imaging algorithm is derived to efficiently process the multichannel data. This algorithm is applied to the simulated radar data to verify the effectiveness of the proposed method. The method is further assessed by applying the imaging algorithm to the radar data acquired from a functional W-band BFD FMCW radar hardware. The radar transceiver was mounted on a movable table, and the data are measured at an outdoor experiment site. The results verify that the proposed method can be used for various 3-D radar imaging applications.

中文翻译：

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使用 W 波段 MIMO 雷达进行三维微波成像的推导和验证


本研究提出了一种使用多输入多输出 (MIMO) 雷达合成 3D 微波图像的方法。最近对 MIMO 雷达技术的研究报告了可用于雷达成像的有前途的硬件。特别是，从 MIMO 雷达获取的数据量的增加对于 3D 雷达成像非常有效。尽管存在使用 3D 雷达成像的需求，但潜在的技术挑战尚未得到解决。尽管阵列合成孔径雷达方法很有前景，但实现具有多个通道的多通道雷达需要在硬件方面付出巨大的努力。因此，使用MIMO雷达可以在减少硬件的情况下有效增加通道数。对拍频分频 (BFD) 调频连续波 (FMCW) 雷达的研究表明，同时传输的 MIMO 信号适用于雷达成像应用，且不会影响沿轨成像性能。在本研究中，根据成像几何形状对安装在可移动平台上的 BFD FMCW 雷达的信号进行建模，并导出基于快速傅立叶变换的成像算法以有效处理多通道数据。将该算法应用于仿真雷达数据，验证了该方法的有效性。通过将成像算法应用于从功能性 W 波段 BFD FMCW 雷达硬件获取的雷达数据，进一步评估该方法。雷达收发器安装在可移动的桌子上，数据是在室外实验场地测量的。结果验证了所提出的方法可用于各种 3D 雷达成像应用。