激光在大气中传输特性的仿真研究

大气对激光传输产生光强闪烁、光束漂移及光斑扩展等影响,严重限制了激光通信、激光测距等系统的工作性能。因此全面开展大气信道中激光传输特性研究是十分重要和必要的。主要研究建立了大气吸收、大气散射衰减效应理论模型及光强起伏、光束漂移和光斑扩展等大气湍流效应影响模型。在分析各模型的基础上,重点进行大气吸收、散射理论模型的仿真和大气湍流对激光传输特性影响模型的仿真。仿真结果表明:大气的吸收和散射将对功率产生衰减;大气抖动引起的激光散斑效应、光束偏折和扩展效应将影响跟踪精度和视轴对准精度;大气湍流引起的光功率波动效应将影响通信的速率和误码率。

Study of Laser Transmission Characteristics in Atmosphere by Simulation

Atmospheric makes the receiver produce laser power attenuation, light intension scintillant beam excursion phenomenon. The operating performances of the laser communication, laser range finder systems and etc. are seriously limited. Now the commonly used theory and research methods in atmosphere transmission characteristics are all based on the research results of foreign countries. Therefore, the research on atmosphere characteristics in the laser transmission channel is very important and necessary. The theory model of the attenuation effect caused by atmosphere absorption, atmosphere scattering, and the effect model of atmospheric turbulence caused by strong light, drifting and expanding of beam and so on are established. Based on the analysis of the above each model, the simulations are focused on the theory model of atmospheric absorption and scattering, and on the effect model of the atmospheric turbulence on the laser transmission characteristics. The simulation results show that atmospheric absorption and scattering will cause power attenuation. Atmospheric jitter of laser speckles effect, beam bending and expanding will influence the tracking accuracy and precision ship-swaying alignment. The fluctuation of power by atmospheric turbulence will affect communication rate and bit error rate. Finally the research on the laser transmission characteristics in the atmosphere is prospected.