Small satellite synthetic aperture radar (SAR) has become a new development direction of spaceborne SAR due to its advantages of flexible launch, short development cycle, and low cost. However, there are fewer researches on distributed small satellite multiple input multiple output (MIMO) SAR. This paper proposes an ultra-high resolution imaging method for the distributed small satellite spotlight MIMO-SAR, which applies the sub-aperture division technique and the sub-aperture image coherent fusion algorithm to MIMO-SAR. After deblurring the sub-aperture signal, the large bandwidth signal is obtained by using an improved time domain bandwidth synthesis (TBS) method, and then the ultra-high resolution image is obtained by using a sub-aperture image coherent fusion algorithm. Simulation results validate the feasibility and effectiveness of the proposed approach.

中文翻译：

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基于子孔径图像融合的分布式小卫星聚光MIMO-SAR超高分辨率成像方法

小型合成孔径雷达（SAR）具有发射灵活，开发周期短，成本低等优点，已成为星载SAR的新发展方向。但是，对分布式小卫星多输入多输出（MIMO）SAR的研究较少。提出了一种用于分布式小卫星聚光MIMO-SAR的超高分辨率成像方法，该方法将子孔径划分技术和子孔径图像相干融合算法应用于MIMO-SAR。在对子孔径信号进行去模糊后，使用改进的时域带宽合成（TBS）方法获得大带宽信号，然后使用子孔径图像相干融合算法获得超高分辨率图像。