团聚形核壳结构冰晶粒子的激光散射特性

地空链路无线光通信链路上，云层是影响激光传输散射特性的主要因素之一，主要是由水滴、冰水或者具有其他混合的核壳结构冰晶粒子等组成。建立了考虑晶核以及中间混合层结构的2、8和39个球形核壳结构团聚冰晶粒子模型，分析了晶核尺寸对于理想团聚形核壳结构冰晶粒子消光、吸收和散射系数的影响；且通过对均匀混合层折射率的计算，对比了纯冰晶、理想核壳和考虑中间混合层的核壳三种多球团聚形冰晶粒子散射强度随散射角度的变化情况。数值结果表明:理想核壳结构和中间混合层的核壳结构对冰晶粒子的散射特性影响较大；相同条件下，三种不同团聚形核壳结构冰晶粒子消光、吸收和散射系数存在显著差异。该研究结果对冰晶粒子的散射特性研究结果更为精确，为开展无线光信号在随机分布冰云中的传输分析奠定理论基础。

Laser scattering properties of agglomerated nucleated shell-structured ice crystallites

On the ground-to-air link wireless optical communication link, the cloud layer is one of the main factors affecting the scattering characteristics of laser transmission. The cloud layer is mainly composed of water droplets, ice water or other mixed core-shell ice crystals. In this paper, a 2, 8 and 39 spherical core-shell structure agglomerated ice crystal sub-models were established considering the crystal nucleus and intermediate mixed layer structure, and the influence of crystal nucleus size on the ice extinction, absorption and scattering coefficients of ideal agglomerated core-shell structure was analyzed. By comparing the refractive index of the uniform mixed layer, the scattering intensity of the three kinds of multi-spheroidal ice crystals with pure ice crystals, ideal core shell and core shell considering the intermediate mixed layer was compared with the scattering angle. The numerical results show that the ideal core-shell structure and the core-shell structure of the intermediate mixed layer have great influence on the scattering characteristics of ice crystal particles. Under the same conditions, there are significant differences in the extinction, absorption and scattering coefficients of ice crystal grains in three different agglomerated core-shell structures. The results of this study are more accurate in the study of the scattering characteristics of ice crystal particles, which lays a theoretical foundation for the transmission analysis of wireless optical signals in random distributed ice clouds.