不同信道环境的激光水下传输仿真

Lasers' Underwater Transmission Simulations in Various Channel Environments

为更深入研究水下激光在武器探测及通信中的应用与不同信道环境传输过程中的特性,验证蒙特卡洛法仿真在水下激光传输中,关于水下散射体直径、密度和距离对接收光子权重、单光子散射次数以及时间展宽的影响,将米氏散射解析模型与蒙特卡罗法仿真结合,通过改变米氏散射模型中的散射体直径、密度以及传输距离从而改变仿真过程中需设置的散射系数、消光系数、不对称因子以及光子自由运动距离,得到其仿真结果关于光子权重随散射体直径、密度以及传输距离的增大而减小的结论,分析了造成其结果的原因;研究了水下散射体直径在蒙特卡洛罗仿真中对单光子平均散射次数的影响。仿真结果表明:在米氏散射模型中单光子散射次数随着散射体直径的增大而增加,分析了散射体直径对造成时间展宽的影响。

In order to further study the underwater laser application in weapon scanning, communication and its characteristics in the various channel environments during the transmission processes, and to verify the influences of the underwater scatterers＇ diameters, density and distance to received photon weight, single photon＇ s scattering number and time broadening with the Monte Carlo method, this thesis combined Mie scattering analytic model with Monte Carlo simulation, and it changed scattering coefficient, extinction coefficient, asymmetry factor and photon＇ s free play distance which should be set in the simulation process to change the Mie scattering analytic model＇ s scatterers＇ diameters, density and transmission distance, resulting in the theory that the photon weight decreases when scatterers＇ diameters, density and transmission distance increase, which is given by simulation report and the reasons of this phenomenon are also be represented with analysis; and we studied the influence of underwater scatterer＇ s diameter to the average scattering numbers of single photon in Monte Carlo simulation. The result shows that single photon＇s scattering number will increase along with the increase of scatterers＇ diameters and it also analyzes the influence of scatterer＇ s diameter to time broadening .