中国激光, 2015, 42 (5): 0513001, 网络出版: 2015-04-28
不同传输环境下大气湍流对无线光通信衰落特性影响分析
Affect Analysis of Atmospheric Turbulence on Fading Characteristics in Free-Space Optical System over Different Environments
无线光通信 大气湍流 公路环境 近海面环境 衰落特性 free space optical communications atmospheric turbulence road environment sea surface environment fading characteristics
摘要
大气湍流引起的光强信号衰落严重影响无线光通信性能。利用大孔径闪烁仪分别对公路环境和近海面环境下大气湍流效应进行测试,在测得的大气折射率结构常数的基础上,对两种环境下无线光通信的衰落特性展开研究。分析了公路环境和近海面环境下大气折射率结构常数的差异,发现前者的湍流强度明显强于后者的湍流强度;在闪烁指数分别取最小值、平均值以及最大值时,研究了准直高斯光束在两种环境下衰落概率的变化特征,得出公路环境下光强信号的衰落程度明显比近海面环境下衰落程度要严重,同时还对衰落概率保持在10-6时,衰落阈值参数的取值情况进行了讨论。
Abstract
Optical intensity signal fading caused by the atmospheric turbulence can severely impact the performance of free space optical communication systems. Large aperture scintillometer is used to test the turbulence effect over the road and sea surface environment. Based on the obtained refractive index structure constant, fading characteristics of free space optical communications are analyzed over these two different environments. The difference of refractive index structure constant under the road environment and the sea environment is analyzed, the result shows that the turbulence intensity of road environment is much stronger than the intensity of sea environment. The change characteristics of probability of fade of colimated Gaussian beam are studied under the two environments, when the scintillation indices are minimum, mean, and maximum, respectively. It shows that the degree of optical signal fading over road is more serious than the degree over sea environment. Fade threshold parameter is discussed when the probability of fade is 10-6.
吴晓军, 王红星, 李笔锋, 宋博. 不同传输环境下大气湍流对无线光通信衰落特性影响分析[J]. 中国激光, 2015, 42(5): 0513001. Wu Xiaojun, Wang Hongxing, Li Bifeng, Song Bo. Affect Analysis of Atmospheric Turbulence on Fading Characteristics in Free-Space Optical System over Different Environments[J]. Chinese Journal of Lasers, 2015, 42(5): 0513001.