中文摘要：

为了研究远距离水平激光链路接收光强起伏的统计特性，进行了16km水平激光传输实验。介绍了大气闪烁的对数正态与伽马-伽马分布模型，根据实验结果分析了孔径接收下信号衰落的统计规律。实验结果表明：伽马-伽马与对数正态分布在较大孔径接收时都能较好地分析远距离传输的光强起伏分布，而且分别是信号性能的上限与下限。采用何种模型要根据实际接收情况，较小孔径接收时，采用伽马-伽马较为准确。由于孔径平均效应和闪烁饱和效应，10^-6衰落几率条件下16km激光链路孔径接收衰落阈值只有6～10dB。

英文摘要：

To study statistical properties of irradiance scintillation of long distance horizontal laser link, a 16 km propagation experiment was carried out. The fading statistics obtained from experimental data were compared to theoretical predictions based on the lognormal and gamma-gamma distributions. It is found that the irradianee scintillation analyzed by the gamma-gamma and lognormal distributions provides an upper and lower signal bound, respectively, under a bigger aperture. While under a smaller aperture receiving condition, only gamma-gamma distribution fits the data well. For effects of irradiance saturation and aperture average, the fading threshold of the 16km laser link is only 6～10 dB under a 10.6 probability of fading.