大气中的分子和气溶胶对紫外光具有强烈的散射作用，因此紫外光在大气中可实现非视距传输。在紫外探测中,收发端的距离较近，为了研究探测过程中紫外光的传输特性，通过蒙特卡罗方法建立多次散射模型，并采用指向概率法对模型进行优化。在收发端轴线共面以及非共面的情况下，对探测到的脉冲响应以及能量密度进行仿真分析，并针对不同大气条件进行仿真。仿真结果表明：紫外激光探测与远距离目标探测不同，偏转角对近距离目标探测的影响较大；在散射系数和吸收系数较大时，收发端距离较近目标的回波信号较强。由仿真结果可以得到紫外光在大气中的传输特性，为今后紫外激光探测的具体设计提供了理论依据。

The molecules and aerosols in atmosphere have a strong scattering effect on ultraviolet light, so the ultraviolet light can propagate in atmosphere in the condition of non-line-of-sight. In the ultraviolet detection, the transmitter is close to the receiver. In order to study the propagation characteristics of ultraviolet light, a multiple-scattering model is established based on the Monte Carlo method, and the model is optimized by the point probability method. The pulse response and the energy density received by the detector in different atmosphere conditions are analyzed through simulation when the axes of transmitter and receiver are coplanar and non-coplanar. The simulation results show that the ultraviolet laser detection is different from remote target detection, and the deflection angle has a great influence on proximate target detection. When the scattering coefficient and absorption coefficient are large and the distance between the transmitter and the receiver is short, the echo signal is strong. The simulation results are helpful to understand the propagation characteristics of ultraviolet light in the atmosphere, and provide the theoretical foundation for the design of ultraviolet laser detection in the future.