无线光自适应副载波MDPSK调制系统特性分析  

Performance Analysis of Wireless Optical Adaptive Subcarrier MDPSK Modulation System

作　　者：陈丹[1] 雷雨 柯熙政[1] CHEN Dan;LEI Yu;KE Xi-zheng(School of Automation and Information Engineering,Xi＇an University of Technology,Xi＇ an,Shaanxi 710048,China)

机构地区：[1]西安理工大学自动化与信息工程学院,陕西西安710048

出　　处：《电子学报》2018年第7期1748-1753,共6页Acta Electronica Sinica

基　　金：国家自然科学基金(No.61671375);陕西省工业攻关科技计划项目(No.2016GY-802);陕西省重点产业创新项目(No.2017ZDCXLGY-06-01)

摘　　要：无线光通信中的自适应传输技术可有效抑制大气湍流引起的信道衰落.根据接收信噪比和预定目标误比特率要求,本文对通过瞬时湍流特性改变调制阶数的无线光自适应传输的通信系统进行了研究.给出采用Malaga分布湍流模型分别描述Gamma-Gamma、对数正态以及K分布湍流信道的相关参数设置;推导了Malaga湍流信道下无线光自适应多进制差分相移键控(MDPSK,M-ary Differential Phase Shift Keying)调制系统的平均误比特率、频谱效率以及中断概率表达式,以及基于Meijer G函数的渐近表达式.MDPSK自适应和非自适应两种调制系统特性分析结果表明:自适应调制系统不但在相同电信噪比下可获得更低的平均误比特率,还可以大大提高频谱效率,而不需要增加额外传输功率或牺牲误比特率.Adaptive transmission technology can effectively inhibit channel fading caused by atmospheric turbulence in wireless optical communications. Under the predefined bit error rate and received signal-to-noise ratio requirement,this paper researched a wireless optical adaptive transmission system due to changing the modulation order through the instantaneous nature of turbulence. Malaga distribution turbulence model is used to describe the distribution of the Gamma-Gamma,Lognormal and K distribution turbulence channel separately,and the related parameters setting methods are given. Analytical expressions of spectrum efficiency,average bit error rate and outage probability under Malaga channel are derived in the adaptive subcarrier M-ary differential phase shift keying（ MDPSK） system. Closed form expressions are also derived based Meijer G function. With the comparison between the performance of adaptive modulation and non-adaptive modulation system,the results showthat the adaptive system can acquire lower BER performance under the same telecom noise ratio,and also improve the spectrum efficiency without additional transmission power or sacrifice bit error rate.

关 键 词：无线光通信 Malaga湍流分布 副载波调制 自适应传输 平均误比特率 频谱效率 

分 类 号：TN929.1[电子电信—通信与信息系统]