基于指向性误差校正技术的自由空间光通信系统BER分析

Bit Error Rate Analysis with Pointing Errors Correction in Free Space Optical Communication Systems

针对指向性误差对自由空间光通信系统性能的影响如误码率以及传统指向性误差校正技术存在的实施难度大等问题,本文在焦面上,基于指向性误差校正技术对FSO系统进行BER分析。首先,讨论了指向性误差校正技术的基本原理,并得到了指向性误差与FSO系统BER之间的关系,设计了一种PID闭环控制算法。其次,搭建了基于PID算法的闭环控制系统,并进行了相关实验。实验结果表明:针对不同大气湍流扰动强度的FSO系统,所述指向性误差校正方法和PID闭环控制算法均具有较好的效果,其中弱扰动情况下的改善效果尤其明显。

Pointing errors caused by the atmospheric turbulence will degrade the performance of free space optical （FSO） communication systems, especially the bit error rate （ BER）, and the traditional pointing errors correction is diffi- cult to implement. To solve those problems, the bit error rate analysis with pointing errors correction technology in free space optical communication systems is done on the focus plane in this paper. Firstly, the basic principle of pointing er- rors correction technology is discussed, the relationship between pointing errors and FSO system BER is obtained. A PID closed-loop control algorithm is designed. Secondly, a closed loop control system is set up based on PID algorithm, and the related experiments are carried on. The experimental results show that the pointing errors correction method and PID closed-loop control algorithm have good effect with different atmospheric turbulence intensity of FSO system, espe- cially under the weak disturbance.