半导体激光通过大气随机信道的二维实时显示与研究

【作者】 许昌武；

【导师】 胡渝； 陈道霞； 邓科；

【作者基本信息】 电子科技大学 ， 光学， 2001， 硕士

【摘要】 随着信息技术的发展，无线光通信因具有容量大、带宽宽、保密性好、抗干扰强、不受FCC控制、机动灵活等优点，使其在组建信息高速公路和空间通信网中成为研究热点，近年来受到国内外普遍重视。近地面无线光通信由于受到大气随机信道的干扰，使得大气信道的研究成为无线光通信的关键技术之一。 本课题针对大气信道的随机特性，主要研究大气随机信道对半导体激光传输的影响。主要内容是：分析了大气的吸收、散射和湍流，用气象上的能见度计算大气的衰减率，把大气近似看作随机介质，分析大气湍流对激光传输的影响；根据激光通过大气信道的传输模型，用软件动态模拟激光在大气中传输时光斑的变化；另外，研制了光斑实时显示系统，二维实时显示半导体激光远场光斑的闪烁和漂移，用此系统进行大量的外场实验，并对实验结果进行了分析总结，讨论实验中发现的孔径效应。最后，还对今后的工作提出设想和希望。更多还原

【Abstract】 With the development of The Information Technology. The Optical Wireless Communications will become a hot pot in the studying of The Space Communication Network and The Information Superhighway for it抯 high capacity, wide band, good security and so on. Many countries have paid attention to it. In near ground optical communication, atmosphere affects the propagation of laser, so we must make a study of the space channel characteristics. This paper is mainly study of the atmospheric influence on the laser transmission for its stochastic behavior. We analyze the scatter. absorption and turbulence of atmosphere. and calculate the atmosphere attenuation ratio by visibility, and we establish the propagation model of laser in the atmosphere. then simulate the scintillation and wander of the laser beam. The real-time display system is introduced which can be used to measure the wander and scintillation of the laser beam. We made some experiments in the sunny days and the foggy days, the experimental results are discussed in the fifth chapter. At last, we give advice for the future work.更多还原