This paper presents two methods, named the irradiance fitting method and the irradiance integration method, for the estimation of refractive index structure constant (C_n²) and extinction coefficient under misalignment. Validations of the methods are carried out based on experimentally obtained speckle images. These two methods are feasible and accurate regardless of whether the optical axis misalignment distance is calibrated, which provides an effective and convenient approach for free space optical communication (FSOC) atmospheric channel research.

中文翻译：

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估计未对准下的折射率结构常数和消光系数

本文提出了两种方法，分别称为辐照度拟合法和辐照度积分法，用于估计未对准时的折射率结构常数（C _n ²）和消光系数。该方法的验证是基于实验获得的斑点图像进行的。无论是否校准了光轴未对准距离，这两种方法都是可行且准确的，这为自由空间光通信（FSOC）大气通道研究提供了一种有效而便捷的方法。