为了研究非视距（NLOS）紫外光通信在雾天环境下的通信性能，针对常见的雾天衰减模型不适用于紫外光大气信道衰减的问题，提出一种新的衰减模型，针对多次散射传输模型计算复杂的问题，提出一种非对称因子的简化计算方法，并使用分集接收技术建立单发多收（SIMO）紫外光通信系统。利用Mie散射理论建立雾天紫外光衰减模型，计算两种雾型在不同浓度下的紫外光衰减参量；提出关于雾滴粒径的非对称因子的简化计算方法；使用等增益合并技术将分集接收的信号合并。采用Monte Carlo法分析SIMO紫外光通信系统性能，并与单发单收（SISO）紫外光通信系统作对比。结果表明，分集接收能有效改善雾天的紫外光通信性能：在厚、中、薄三种雾天中，SIMO紫外光通信系统的最远通信距离比SISO通信系统分别大约5，10，10 m；SISO紫外光通信系统误码率为10^-3时，SIMO通信系统误码率可降低到约10^-5。

To study the communication performance of non-line-of-sight (NLOS) ultraviolet (UV) communication in foggy environments, we propose a new attenuation model and a simplified calculation method of asymmetric factors. These solve the problems that the common fog attenuation model is not suitable for ultraviolet atmospheric channel attenuation and the calculation of multiple scattering transmission model is complex. A single-input-multiple-output (SIMO) ultraviolet communication system is established using the diversity receiving technology. First, a UV attenuation model is developed based on the Mie scattering theory to calculate the UV attenuation parameters of two fog types at different concentrations. Second, the asymmetric factor of a droplet size is established to simplify the calculation. Finally, the equal-gain combining technique is used to combine the diversity received signals. The performance of the SIMO UV communication system is analyzed by the Monte Carlo method and compared with that of the SISO UV communication system. The results show that diversity reception can effectively improve the performance of ultraviolet communication on foggy days: on thick, medium and thin fog days, and the maximum communication distance of the SIMO communication system is about 5, 10, and 10 m longer than that of a SISO communication system, respectively. When the bit error rate of the SISO ultraviolet communication system is 10^-3, the bit error rate of the SIMO communication system is reduced to about 10^-5.