大气扰动引起波前畸变是地基光学望远镜的像质退化的主要原因。图像统计重建方法能够有效消除大气这一影响。因此，在天文目标重建方面里已得到了广泛的应用。其中，迭代位移叠加法（Iterative Shift and Add ——ISA），这一空域统计重建算法，是目前比较成功的天文图像统计重建算法，而且已经实现了面源目标的重建。然而，在对太阳，大的卫星等面源目标重建时不能观测到参考点源，所以需要研究ISA算法的传递函数的数学模型，这便是本论文的研究的内容之一，为ISA算法的传递函数建立精确的模型。 本文采用数值模拟的方法研究ISA算法的传递函数特性。在只考虑大气湍流对光波经过大气-望远镜综合系统成像的影响情况下，模拟了不同大气相干参数的迭代位移叠加法的统计点扩展函数。通过曲线拟合得到迭代位移叠加法(ISA)的平均功率谱，进而得到理想条件下的光学传递函数。 本论文要研究的另一部分内容是提出了一种可以模拟等晕区效应的多层大气相位屏的数值模拟方法，这种方法可以应用于等晕区对高分辨统计重建方法的影响的研究中。利用该模拟方法模拟了5个角秒和8个角秒的双星，通过比较模拟目标与实测目标的斑点干涉术的结果得到结论：该数值模拟方法所产生的等晕区效应与实际的等晕区效应相似。同时，分析了等晕区对ISA算法的影响，给出了受到等晕区效应影响的平均功率谱。
其他摘要
Atmospheric turbulent aroused the degradation of image quality of the ground-based telescope. Statistical image reconstruction methods could eliminate the effect of the atmospheric. For this reason, it has been a wildly applications in the field of astronomy object reconstructed. Among these methods, Iterative Shift and Add (ISA), the spatial frequency statistical reconstructed method, is a more successful statistical reconstruction algorithm, on the Double Star, Triple and other objectives of the reconstruction of point sources to achieve a resolution of the telescope diffraction limited. However, the mathematical models of the transfer function about Iterative Shift and Add method isn’t well described. One purpose of the paper is obtaining the model of transfer function about Iterative Shift and Add (ISA). The paper use the numeral simulation method, just considered the turbulence effect, simulate the statistical results of the Iterative Shift and Add method at different atmosphere coherent length. Then obtained the average power spectrum by curve fitting, at last, established the optical transfer function under the ideal conditions. The other partial of this paper is proposed a kind of numeral computer simulation method by modeling multiple atmospheric phase screens, to simulate the isoplanatic effect. This method could be applied to research the isoplanatic effect on the high-resolution statistical reconstruction algorithm. With this simulation method the speckle of Binary separated 5 arc-second and 8 arc-second are modeled, the reconstructed results of Speckle Inerferometry between the simulation binary and the observed Binary are compared. The result shows that the isoplanatic effect aroused by the simulation method is similar to the actual one. Meanwhile, analysis the isoplanatic effect on the ISA method, then, draw up the power spectrum curve which influenced by the isoplanatic effect.
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