大气气溶胶对激光传输衰减的影响研究

在大气气溶胶类型、谱分布的基础上,利用Mie散射理论计算气溶胶在可见光和近红外波段的散射和衰减特性,讨论分析了大气气溶胶对可见光和近红外波段激光传输衰减的影响,计算结果表明,激光传输在很大程度上受粒子的折射率和谱分布的影响；不同类型气溶胶粒子具有不同的折射率和谱分布参数,从而决定了其具有不同的散射和吸收特性；气溶胶粒子的数密度越大,其衰减和散射能力就越强,对激光传输的衰减也就越大；但前后向散射的不对称性只与气溶胶谱分布有关,与数密度无关.所得出的结论有助于准确评估大气气溶胶对激光传输的影响以及提高激光传输、通信和激光测风等应用.

Effect of Atmospheric Aerosols on Laser Transmission Attenuation

Based on the size distribution of atmospheric aerosols,the scattering characteristics of aerosols at visible and infrared wave band are calculated by Mie scattering theory,the effects of aerosols on the laser transmission attenuation at visible and infrared wave band are discussed.The numerical simulation results show that the scattering characteristics of aerosols are sensitive to the types and size distributions of aerosols; the laser transmission attenuation are affected not only by the refractive index and types,but also by number density of aerosols.The more the number density,the stronger the laser transmission attenuation will be; while the asymmetry parameter is insensitive to the number density,which is mainly influenced by the size distribution.These results are beneficial to evaluate the effect of aerosols on laser transmission,which will promote the application of laser signal transmission,communication and wind measurement by laser.