大气湍流下无线光通信信道性能研究

无线光通信中大气湍流导致光信号在传输中产生光强起伏等现象，其影响成为无线光通信普及的一大障碍．基于大气湍流不同光强起伏信道模型，分别建立了弱、中及强湍流信道的中断概率与平均信道容量数学统计模型，研究了大气折射率结构常数和传输距离对湍流信道可靠性的影响．仿真结果表明，归一化闽值信噪比和通信距离的增加导致通信系统性能劣化．平均信道容量随着湍流强度的增大而降低，且随着接收机平均电信噪比增大，弱湍流下的信道容量增长速度明显大于强湍流．

Performance of Wireless Optical Communication over Atmospheric Turbulence Channel

Based on different scintillation distribution channel model over atmospheric turbulence, the statistic model of outage probability and average channel capacity was founded, and the method on Gauss -Lager was applied to calculate outage probability and average channel capacity under weak to moderate and moderate to strong turbulence. The simulation results showed that outage probability increases with the increasing intensity of turbulence and normalized average electrical SNR, and average channel capacity also increases with the increasing of receiver average electrical SNR. The increasing rate is faster and channel capacity is biger under weak turbulence than strong turbulence. The knowledge of the theory was provided for wireless optical access communication system.