In this paper, the challenges of parameter estimation for the Gamma-Gamma turbulence channels with generalized pointing errors are addressed. The Kolmogorov-Smirnov goodness-of-fit statistical test results indicate that the approximate probability density function obtained by the saddlepoint approximation (SAP) method provides a better approximation for a larger value , and this means that the proposed method is more efficient for the FSO links over long distances when the transmit divergence angle at the transmitter side is fixed. Also, an additional parameter needs to be estimated in addition to the shaping parameters and under the SAP method. An estimation scheme for the shaping parameters is proposed based on the SAP method. The performance of the proposed estimation is investigated by using the mean square error (MSE) and normalized mean square error (NMSE). The results indicate the proposed estimator exhibits satisfactory performance in both noiseless and noisy environments. The effects of the receiver aperture on the estimation performance are also discussed.

中文翻译：

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FSO系统中具有广义指向误差的Gamma-Gamma衰落的参数估计

在本文中，解决了具有广义指向误差的 Gamma-Gamma 湍流通道参数估计的挑战。Kolmogorov-Smirnov 拟合优度统计检验结果表明，鞍点近似（SAP）方法得到的近似概率密度函数为较大的值提供了更好的近似，这意味着所提出的方法对 FSO 更有效当发射端的发射发散角固定时，长距离链路。此外，除了整形参数和参数之外，还需要估计一个附加参数。在 SAP 方法下。提出了一种基于SAP方法的整形参数估计方案。通过使用均方误差 (MSE) 和归一化均方误差 (NMSE) 来研究所提出的估计的性能。结果表明，所提出的估计器在无噪声和噪声环境中均表现出令人满意的性能。还讨论了接收器孔径对估计性能的影响。