无线光通信中自适应偏置混合ACO-OFDM方法研究  

Research on the adaptively biased hybrid ACO-OFDM method in optical wireless communications

作　　者：陈缪龙 钱诚成 李宝龙 CHEN Miaolong;QIAN Chengcheng;LI Baolong(Changwang School of Honors,Nanjing University of Information Science&Technology,Nanjing,Jiangsu 210044,China;School of Electronic and Information Engineering,Nanjing University of Information Science&Technology,Nanjing,Jiangsu 210044,China)

机构地区：[1]南京信息工程大学长望学院,江苏南京210044 [2]南京信息工程大学电子与信息工程学院,江苏南京210044

出　　处：《光电子．激光》2024年第12期1300-1306,共7页Journal of Optoelectronics·Laser

基　　金：国家自然科学基金(62201275);江苏省自然科学基金(BK20190582);南京信息工程大学人才启动经费(2021r084)资助项目。

摘　　要：针对混合非对称限幅光学正交频分复用(hybrid asymmetrically clipped optical orthogonal frequency division multiplexing,HACO-OFDM)技术只利用了奇数子载波和偶数子载波的虚部进行符号传输而导致频谱效率低效的问题,本文提出了一种自适应偏置HACO-OFDM(adaptively biased HACO-OFDM,AB-HACO-OFDM)方法。该方法针对未被使用的偶数子载波的实部,构造了脉冲幅度调制离散多音(pulse-amplitude modulated discrete multitone,PAM-DMT)信号,并与HACO-OFDM信号混合传输提升子载波利用率,同时,引入功率高效的自适应偏置信号保证非负性。仿真结果表明:相比HACO-OFDM,提出的AB-HACO-OFDM能够有效地提升传输的频谱效率,同时,具有更优的误比特率(bit error rate,BER)性能。此外,相比传统的正交频分复用(orthogonal frequency division multiplexing,OFDM)方法,所提方法实现目标BER所需的信噪比更低,表现出更高的功率效率。The hybrid asymmetrically clipped optical orthogonal frequency division multiplexing(HACOOFDM)technique only utilizes the odd subcarriers and the imaginary part of the even subcarriers for symbol transmission,leading to the problem of low spectral efficiency.To address this problem,an adaptively biased HACO-OFDM(AB-HACO-OFDM)method is proposed.In the proposed method,a pulse-amplitude modulated discrete multitone(PAM-DMT)signal is designed for the unused real part of the even subcarriers,and is further superimposed on the HACO-OFDM signal for hybrid transmission to enhance the subcarrier utilization.Meanwhile,a power-efficient adaptive bias signal is introduced to guarantee the non-negativity.The simulation results demonstrate that compared to HACO-OFDM,the proposed AB-HACO-OFDM is capable of effectively improving the spectral efficiency of the transmission,while at the same time,achieving better performance in bit-error rate(BER).Additionally,compared to the conventional orthogonal frequency division multiplexing(OFDM)methods,the proposed method requires much lower signal-to-noise ratio to achieve the BER of target,thus exhibiting higher power efficiency.

关 键 词：无线光通信 正交频分复用(OFDM) 混合非对称限幅光正交频分复用(HACO-OFDM) 频谱效率 

分 类 号：O436[机械工程—光学工程]