沙尘天气下大气能见度对激光光强的影响

Impact of Atmospheric Visibility on Laser Intensity in Sand and Dust Weather

基于米氏理论,分别研究了不同波长的激光信号在沙尘天气中发生单次散射和多次散射时光强与能见度间的变化关系.推导出发生单次散射时光强与能见度间的解析表达式,同时采用蒙特卡洛方法分析了发生多次散射时光强与能见度间的关系,并与单次散射时的结果进行对比.结果表明:在激光信号波长固定时,接收光强会随着沙尘能见度的增大而增加,并趋于稳定值;在能见度固定时,接收光强会随着激光信号波长的增大而减小;随着传输距离的增加,多次散射的影响会越来越明显.

The relationship of atmospheric visibility to laser intensity was analyzed based on Mie theory under the conditions of single scattering and multiple scattering scenarios in sand and dust weather.An improved analytical expression of laser intensity and atmospheric visibility was derived in single scattering scenario.The multiple scattering was simulated by Monte Carlo method and compared with single scattering.The results show that the received laser intensity will be increased with the increment of atmospheric visibility and approximate to a saturated value when the laser wavelength and transmission distance is constant.Moreover,when the atmospheric visibility remain unchanged,the received laser intensity will be decreased with the increment of laser wavelength,and with the increase of transmission distance,the influence of multiple scattering will become more and more notable.