无线光通信系统中64-QAM调制实验研究  

Research on 64-QAM subcarrier modulation for optical wireless communication

作　　者：柯熙政[1] 解孟其[1] 石碧瑶 Ke Xizheng;Xie Mengqi;Shi Biyao(School of Automation and Information,Xi＇an University of Technology,Xi＇an 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：《红外与激光工程》2018年第A01期68-73,共6页Infrared and Laser Engineering

基　　金：国家自然科学基金（61377080）;国家科技创新基金（13C26213201867）;陕西省重点产业创新项目（2017ZDCXL-GY-06-01）

摘　　要：高阶QAM较BPSK／QPSK能在有限的带宽内能传输更多的信息量，因此广泛应于有线通信系统中。而对于无线光通信，大气湍流引起的光强闪烁效应对高阶QAM信号的影响很大，本文采用多模盲均衡算法克服此类噪声。系统仿真中使用Gamma-Gamma模型模拟大气湍流信道，对比了不同噪声情况下接收信号星座图的聚敛性，结果表明在传输过程中影响信号质量的主要因素是乘性噪声。最后搭建了64-QAM实验系统证明上述算法的可行性。High-order Quadrature Amplitude Modulation （QAM） in a limited bandwidth can transmit more information than either BPSK or QPSK system. Therefore, the technology is widely used in cable communication systems. While optical scintillation affected the high-order QAM system easily. The multi- mode blind signal equalization is used to reduce the influence of scintillation caused by atmospheric turbulence. In simulation, the turbulence channel was modeled by Gamma-Gamma distribution. The constellation of receiving signal shows the different points dispersions under different channel noise situations. Results show that the transmitted signal was primarily affected by multiplicative noise. A 64- QAM experimental system is built to demonstrate the feasibility of the system under real situation.

关 键 词：64-QAM调制解调 信道噪声 星座图 自由空间光通信 MMA均衡 

分 类 号：TN929.1[电子电信—通信与信息系统]