雨滴谱模型对雨衰减计算的适用性分析

Raindrop size distribution model for applicability analysis of rain attenuation

雨滴谱分布模型是影响红外激光在雨中传输性能的一个重要因素。尽管现有的雨滴谱模型很多,但并未形成统一的结论,具体应用中模型的选择没有依据,使得计算中模型的选择具有一定的盲目性。针对此问题,论文从Mie散射理论出发,采用理论分析与仿真分析相结合的方法,讨论了几种雨滴的谱分布特性,比较了几种典型雨滴谱模型下的光传输衰减特性,分析了雨滴尺寸分布在计算大气衰减时的差异。并通过与实测雨衰减数据进行比较,最终得到了L-P模型对大雨条件下的衰减计算较为准确,Joss模型对小雨条件下的衰减计算较为准确的结论。论文的结论对于无线光通信等应用领域中模型的合理选择具有一定的指导意义。

Rain dropsize distribution model is an important factor that affects transmission performance of infrared and laser in the rain. Although many rain dropsize distribution models exist at present, yet it has not formed a common conclusion and there is no basis for model selection in specific applications. That makes some calculations and design work difficult. In view of this problem, the paper starts from the Mie scattering theory, combining theoretical analysis with simulation, to discuss several kinds of raindrop spectrum distribution characteristics. Attenuation characteristics of some typical rain dropsize distribution models are compared. By comparing the analysis results with the actual rain atenuation data,it comes to the conclusion that the LP model is more accurate for heavy rain and the Joss model is more accurate for light rain. Some conclusions are helpful for choosing model when analyzing optical systems such as wireless optical communication.