SIAM Journal on Imaging Sciences, Volume 13, Issue 3, Page 1331-1366, January 2020.
We consider imaging of fast moving small objects in space, such as low earth orbit satellites or satellite debris. The imaging system consists of ground based, asynchronous sources of radiation and several passive receivers above the dense atmosphere. We use the cross correlation of the received signals to reduce distortions from ambient medium fluctuations. Imaging with correlations also has the advantage of not requiring any knowledge about the probing pulse and depends weakly on the emitter positions. We account for the target's orbital velocity by introducing the necessary Doppler compensation. We show that over limited imaging regions, a constant Doppler factor can be used, resulting in an efficient data structure for the correlations of the recorded signals. We then investigate and analyze different imaging methods using the cross-correlation data structure. Specifically, we show that using a generalized two-point migration of the cross-correlation data, the top eigenvector of the migrated data matrix provides superior image resolution compared to the usual single-point migration scheme. We carry out a theoretical analysis that illustrates the role of the two-point migration methods as well as that of the inverse aperture in improving resolution. Extensive numerical simulations support the theoretical results and assess the scope of the imaging methodology.

中文翻译：

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基于广义相关性的卫星成像

SIAM影像科学杂志，第13卷，第3期，第1331-1366页，2020年1月。
我们考虑对空间中快速移动的小物体（例如低地球轨道卫星或卫星碎片）进行成像。该成像系统由基于地面的异步辐射源和在浓密大气上方的多个无源接收器组成。我们使用接收信号的互相关来减少环境介质波动引起的失真。具有相关性的成像还具有不需要关于探测脉冲的任何知识的优点，并且弱地依赖于发射器的位置。我们通过引入必要的多普勒补偿来考虑目标的轨道速度。我们表明在有限的成像区域上，可以使用恒定的多普勒因子，从而为记录信号的相关性提供有效的数据结构。然后，我们使用互相关数据结构调查和分析不同的成像方法。具体而言，我们表明，使用互相关数据的广义两点迁移，与通常的单点迁移方案相比，迁移后的数据矩阵的顶部特征向量可提供更高的图像分辨率。我们进行了理论分析，阐明了两点偏移方法以及反孔径方法在提高分辨率中的作用。广泛的数值模拟支持理论结果并评估成像方法的范围。与通常的单点迁移方案相比，迁移数据矩阵的顶部特征向量可提供更高的图像分辨率。我们进行了理论分析，阐明了两点偏移方法以及反孔径方法在提高分辨率中的作用。广泛的数值模拟支持理论结果并评估成像方法的范围。与通常的单点迁移方案相比，迁移数据矩阵的顶部特征向量可提供更高的图像分辨率。我们进行了理论分析，阐明了两点偏移方法以及反孔径方法在提高分辨率中的作用。广泛的数值模拟支持理论结果并评估成像方法的范围。