摘要
为了进一步确定降雨对激光在大气中传输衰减的影响,将雨滴的非球形效应考虑在内,在雨滴的近似椭球模型、归一化谱分布的基础上,利用射线追踪法计算群雨滴在可见光和近红外波段的散射和衰减特性,讨论分析雨滴谱分布和降雨强度对可见光和近红外波段激光传输衰减的影响。数值模拟结果表明,不同谱分布的群雨滴散射能力从大到小依次为JD、MP、Gamma和JT分布;激光衰减不仅受降雨强度的影响,也与雨滴的数密度有关,数密度越大,激光衰减越大;而形状对群雨滴的影响较小。所得出的结论有助于准确评估降雨对激光传输的影响以及改善激光传输、通信和激光测风等应用。
To examine the effect of the non-spherical raindrops on laser transmission attenuation in atmospheric, based on the approximate ellipsoid model of raindrops and normalized raindrops size distribution, the scattering characteristics of raindrops cluster in the visible and infrared domain were calculated by ray-tracing method. The effects of raindrop size distribution and rainrate on the laser transmission attenuation were discussed. The numerical simulation results show that the scattering capabilities of raindrops cluster decrease in the order of JD, MP, Gamma and JT; the laser transmission attenuation are not only affected by the rainrate, but also affected by number density of rainfall, the more the raindrops, the stronger the laser transmission attenuation; while the effect of shape of raindrops is relative small. These results will be benefit to evaluate the effect of precipitation on laser transmission, which will promote the application of laser signal transmission, communication and wind measurement by laser.
出处
《红外与激光工程》
EI
CSCD
北大核心
2013年第1期167-173,共7页
Infrared and Laser Engineering
基金
国家自然科学基金(41076118
41205125)
关键词
激光传输衰减
近似椭球雨滴
雨滴谱分布
射线追踪法
attenuation of laser transmission
raindrop of approximate ellipsoid model
raindrop size-distribution
ray-tracing method
