Gamma-Gamma信道下混合调制超奈奎斯特大气光通信系统的误码率性能  

Bit Error Rate Performance of Hybrid Modulated Faster-Than-Nyquist Atmospheric Optical Communications Under Gamma-Gamma Channel

作　　者：曹明华[1] 吴照恒 张伟 邱艳 夏皆平 陈丹[2] 王惠琴[1] Cao Minghua;Wu Zhaoheng;Zhang Wei;Qiu Yan;Xia Jieping;Chen Dan;Wang Huiqin(School of Computer and Communication,Lanzhou University of Technology,Lanzhou 730050,Gansu,China;School of Automation and Information Engineering,Xi’an University of Technology,Xi’an 710048,Shaanxi,China)

机构地区：[1]兰州理工大学计算机与通信学院,甘肃兰州730050 [2]西安理工大学自动化与信息工程学院,陕西西安710048

出　　处：《激光与光电子学进展》2022年第13期165-171,共7页Laser & Optoelectronics Progress

基　　金：国家自然科学基金(61875080,61861026);甘肃省科技计划(20JR5RA472)。

摘　　要：脉冲位置调制(PPM)具有简单、抗干扰能力强等优点,但存在频带利用率不高的缺点。为了提高系统的频带利用率和传输速率,设计了一种相移键控(PSK)与PPM相结合的混合调制超奈奎斯特(PSK-PPM-FTN)速率大气光通信方案。推导了该方案在Gamma-Gamma分布大气信道下的误码率(BER)公式,并分析了BER与传输距离、波长以及时间加速因子τ之间的关系。蒙特卡罗仿真结果表明:将高阶PPM与多进制PSK相结合,能在τ≥0.8的水平通信链路中以较小的BER为代价传输更多的信息;当τ=0.8时,正交相移键控-4阶脉冲位置调制-超奈奎斯特速率(QPSK-PPM4-FTN)传输的信息量相较于QPSK提高了1.5倍,系统带宽利用率相较于PPM4提高了150%。Pulse-position modulation(PPM)has the advantages of simplicity and high interference immunity but is affected by the issues concerning low frequency band utilization.To improve the system’s bandwidth utilization and data transmission rate,a hybrid modulated faster-than-Nyquist(PSK-PPM-FTN)rate atmospheric optical communication scheme in combination with phase-shift keying(PSK)and PPM is proposed in this paper.The bit error rate(BER)is derived over Gamma-Gamma-distributed atmospheric channel.In addition,the relationship of BER and transmission distance,laser wavelength,and time acceleration factor τ is analyzed.Monte Carlo simulation results show that when highorder PPM is combined with multi-ary PSK,and additional information can be transmitted at the cost of a slight drop in BER performance in a horizontal communication link withτ≥0.8.When τ=0.8,the amount of information,which is transmitted by a quadrature PSK-PPM4 FTN(QPSK-PPM4-FTN)scheme,is 1.5 times than that of QPSK,and the system bandwidth utilization is 150% higher than that of PPM4.

关 键 词：光通信 混合调制 误码率 超奈奎斯特速率 

分 类 号：O436[机械工程—光学工程]