大气湍流对激光通信系统性能的影响研究

陈牧，柯熙政

(西安理工大学自动化与信息工程学院，陕西西安710048)

摘要:大气湍流引起的光强起伏是影响激光通信系统接收信噪比和误码率的主要因素。文中旨在研究大气湍流状态对无线通信系统性能的影响。首先利用对数正态分布和Gamma-Gamma 分布分别对信道进行建模，分析表明前者不适用于中强湍流下的光强起伏行为，而后者具有更广的应用范围。在此基础上，研究相位噪声对系统接收信噪比和误码率的影响。文中最后在不同信道条件下进行仿真实验，观察光强起伏方差引起的星座图变化和误码率恶化情况。实验结果表明，当光强起伏方差逐渐增大时，星座图相位角度和误码率均随之变大。文中的分析与讨论对提高激光通信质量具有一定的参考价值。

关键词:激光通信；大气湍流；光强起伏；相位噪声；误码率

中图分类号:TN929.12文献标志码:A DOI :10.3788/IRLA201645.0822009

Effect of atmospheric turbulence on the performance of laser

communication system

Chen Mu,Ke Xizheng

(School of Automation and Information Engineering,Xi′an University of Technology,Xi′an 710048,China)

Abstract:The irradiance fluctuation induced by atmospheric turbulence is a major factor to degrade the Signal-to-Noise Ratio (SNR)and bit error rate (BER)of laser communication systems.This paper aims to explore the effect of atmospheric turbulence state on the performance of wireless communication systems.Firstly,the channel was modeled by the logarithmic normal distribution and Gamma -Gamma distribution,respectively.Analysis showed lights on that the former model was not fit for irradiance fluctuation behavior in moderate or strong turbulent conditions,while the latter had wider applications.On this basis,the SNR and BER resulting from the phase noise introduced by irradiance were studied.Simulations were conducted for different channel models,which displayed the change of planisphere and degradation of BER along with irradiance variance.Results illustrates that the phase angle of planisphere and BER increase when the irradiance variance becomes larger.Up to a point,these discussions are valuable for real optical communication applications.

Key words:laser communication;

atmospheric turbulence;irradiance fluctuation;phase noise;

bit error rate

收稿日期:2015-12-05;修订日期:2016-01-08基金项目:国家自然科学基金(60977054);陕西省“13115”科技统筹计划(2011KTCQ01-31);

陕西省教育厅产业化培育基金(2010JC17);

作者简介:陈牧(1989-),男,博士生,主要从事相干光通信中噪声模型研究。Email:chenmuaj@https://www.360docs.net/doc/a716344100.html,

导师简介:柯熙政(1962-),男,教授,博士生导师,博士,主要从事无线光通信方面的研究。Email:xzke@https://www.360docs.net/doc/a716344100.html,

0822009-1第45卷第8期

红外与激光工程2016年8月

Infrared and Laser Engineering