无线光通信卷积交织与编码的实验及仿真研究

Experimental and simulation study on convolutional interleaving with coding for optical wireless communication system

大气光强闪烁会明显降低无线光通信的通信质量。为了降低这种影响,进行了卷积交织结合(1/2,7)卷积编码用于无线光通信系统的实验及仿真研究,完成了相应的实验光机和通信电路的研制,设计了OOK方式调制785nm半导体激光器的方案应用于室外无线光通信系统。理论和实验结果都表明,设计的差错控制编码技术在弱湍流条件下,较好地提高无线光通信系统的通信性能。此外,外场实验和仿真结果还反映出,大气湍流引起的光信号的深衰落会明显影响系统的通信误码率,提高交织器的交织深度可以有效地抑制其影响。

Intensity fluctuations induced by atmospheric turbulence impair the performance of optical wireless communication significantly. To mitigate these negative effects, channel coding scheme of convolutional interleaving with （1/2, 7） convolutional coding was studied for the optical wireless communication system. Moreover, optical terminals and communication circuits had been designed for outdoor optical wireless communication using OOK modulation on 785nm semiconductor laser. The experimental results correspond well with the simulation prediction that the error control coding can improve the quality of the optical wireless communication system under weak turbulence. In addition, by increasing the interleaving depth, the impact of long deep fade durations can be further reduced.