AI 中文总结
针对卫星成像，提出一种基于残余倾斜、目标通量与噪声水平等参数确定最优曝光时间的方法，以平衡散斑信息保留与信噪比，减少抖动影响，优化后处理图像质量。
AI 中文摘要
自适应光学辅助的天文成像与地面卫星成像有许多共同点，但也有各自的特点。特别是，卫星在形状和通量上都是非平稳目标，这促使采用相对较短的曝光时间。此外，非常短的曝光会冻结湍流并在散斑中保留高频空间信息，但代价是图像信噪比低，这使后处理变得复杂。相反，长曝光会产生无散斑的图像，其中一些高频信息会丢失。在本通讯中，我们提出了一种确定曝光时间的方法，以优化后处理后的图像质量。我们特别关注减少抖动效应——由大气倾斜残余、振动和目标非平稳性引起——这些效应在成像卫星时可能显著降低图像质量。我们的模型考虑了目标类型和通量、残余像差的功率谱密度以及噪声水平。
英文摘要
Adaptive-Optics assisted astronomical imaging and satellite imaging from the ground share many commonalities but have also specificities. In particular satellites are non-stationary objects in terms of both shape and flux, encouraging relatively short exposure times. Besides, very short exposures freeze the turbulence and preserve high spatial frequency information in speckles, but at the cost of a low image SNR, which complicates the post-processing. Conversely, long exposures lead to speckle-less images where some high frequency information is lost. In this communication, we propose a method for determining the exposure time that optimizes the image quality after post-processing. In particular, we focus on the reduction of the jitter effects -- induced by atmospheric tip-tilt residues, vibrations and object non stationarity -- which may dramatically reduce the image quality when imaging satellites. Our model takes into account the object type and flux, the residual aberrations power spectral density and the noise level.
Journal refAstronomical Telescopes + Instrumentation, SPIE, Jul 2026, Copenhagen, Denmark. pp.14150-310
