中文摘要：

分析了雾产生的原因、相关数学模型及其对大气激光通信系统的影响,为了克服雾对无线光通信链路的影响，将LDPC码作为信道编码应用到大气激光通信系统中，并结合置信传播迭代译码算法和副载波PSK强度调制方案，在有雾的大气信道中进行了仿真。仿真结果表明：LDPC码具有优越的纠错能力,并获得了较大的编码增益，上述方案可以满足大气激光通信系统的需要。

英文摘要：

The causes of fog, the relevant mathematical models and its influence on atmospheric laser communication system are analyzed. In order to overcome the influence of fog on wireless optical communication link, the LDPC codes as channel coding are applied into atmospheric laser communication system, and it is simulated in the foggy atmospheric channel with combination of BP iterative decoding algorithm and sub-carrier PSK intensity modulation. The simulation results show that LDPC codes have excellent error correction capabilities and access to a larger coding gain,and the proposed scheme can satisfy the need of atmospheric laser communication system.