海洋大气湍流对激光通信系统性能的影响分析

大气湍流引起光波强度在光束截面内的闪烁,降低了激光通信系统的信噪比.应用基于Rytov近似的激光大气传输光强起伏理论模型,在局地均匀各向同性Kolmogolov湍流谱的假设条件下,对大气湍流引起的光强起伏进行了分析.并从信号检测理论出发,将大气湍流与激光通信系统误码率指标相结合.分析结果表明,在典型的海洋大气湍流环境下,以误码率指标衡量,随着C2n的增加,激光通信系统的有效作用距离大大缩短,当C2n达到5×10-15m-2/3时,通信的有效距离不足2 km,当C2n达到3×10-14m-2/3时,通信的有效距离降至1 km以下.

Research on the Influence of Marine Atmospheric Turbulence to the Performance of Laser Communication System

Light intensity fluctuation in the cross-section caused by atmospheric turbulence increases the bit error rate(BER) of laser communication system. The effect is analyzed using the theory of light propagation in the atmosphere based on the Rytov approximation under the suitable assumptions of isotropic Kolmogolov spectrum of turbulence, and the BER of laser communication system and atmospheric turbulence are combined in terms of signal detection theory. The analysis results turn out that, measured by BER, the effective distance of laser communication system shortens greatly along with the increasing of EQUATION] under the environment of typical marine atmospheric turbulence, the effective distance is less than 2 km when EQUATION] is equal to 5EQUATION] mEQUATION], and the distance even shortens to 1 km when EQUATION] reaches 3EQUATION] mEQUATION].