概率整形作为一种新兴编码技术，通过改变各星座点的概率分布来获得整形增益，能够提高通信系统的性能。本文阐述概率整形的基本原理，通过互信息、误码率与信噪比的关系曲线，展示概率整形编码相较均匀分布编码带来的性能提升。重点探究了在带宽受限的光纤通信信道中，概率整形对系统传输性能的影响。仿真结果表明，在带宽受限条件下，概率整形对系统的误码性能和带宽容忍度都有提升作用。
Probabilistic shaping is an emerging coding technique, by changing the probability distribution of constellations，it can obtain the shaping gain and improve the performance of communication system. The principle of probabilistic shaping is presented, and the performance improvement brought by probabilistic shaping coding compared with uniform distribution coding is demonstrated through the relationship curve between mutual information, bit error rate and signal-to-noise ratio. Subsequently, the effect of probabilistic shaping in bandwidth limited optical communication system is studied. The simulation results show that in bandwidth limited condition, probabilistic shaping brings a promoting both to the system’s BER performance and bandwidth tolerance.
2020,42(3): 136-138,189 收稿日期：2019-12-18
DOI：10.3404/j.issn.1672-7649.2020.03.028
分类号：TN913
基金项目：高速短距离光传输中非线性估计与信号均衡（61601430）
作者简介：王瑞(1995-),男,硕士研究生,主要研究方向为光通信技术。
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