大气信道部分相干光通信链路性能分析与优化

Performance Analysis and Optimization of Partially Coherent Optical Communication Links Through Atmospheric Channel

针对使用开关键控的强度调制/直接检测部分相干光链路,建立了信道容量、信道误码率以及链路中断概率的数学分析模型.在此基础上,分别对完全相干光和部分相干光链路的信道容量、信道误码率以及链路中断概率进行了计算和对比分析.给出了发射功率受限时,光束初始相干度的优化选取模型.在大气湍流信道中,部分相干光通信的性能优于完全相干光通信,部分相干光传输是一种有效的大气湍流影响抑制技术.

Focusing on intensity-modulation/direct-detection （IM/DD） partially coherent optical links using the on-off-keying scheme, the analytic models of channel capacity, channel bit-error-rate and link outage probability were established. On the basis of these models, the calculations of channel capacity, channel bit-error-rate and link outage probability for both fully and partially coherent optical links were performed,and then the comparative analysis for the two types of links was presented. The optimization tion model for the initial coherent degree of a laser was proposed with the situation when the transmitted power was limited. The performance of optical links through atmospheric turbulence using partially coherent beams is better than fully coherent beams, and propagation using a partially coherent beam is an effective technique for mitigating the turbulence-induced impact.