DCO-OFDM系统中导频辅助峰均比抑制技术  

Pilot-assisted PAPR reduction technique for DCO-OFDM systems

作　　者：唐芳 徐智勇 汪井源 赵继勇 李建华 TANG Fang;XU Zhi-yong;WANG Jing-yuan;ZHAO Ji-yong;LI Jian-hua(Institute of Communications Engineering,PLA Army Engineering University,Nanjing Jiangsu 210007,China)

机构地区：[1]解放军陆军工程大学通信工程学院

出　　处：《光电子．激光》2019年第10期1116-1122,共7页Journal of Optoelectronics·Laser

基　　金：江苏省光通信工程与技术研究中心计划项目(ZXF20170101)资助项目

摘　　要：为了降低直流偏置光正交频分复用(DC-biased Optical OFDM,DCO-OFDM)系统中高峰均功率比(Peak to Average Power Ratio,PAPR)对无线光通信系统性能的影响,本文提出一种导频辅助峰均比抑制方案。方案中将多个离散频域信号划分为多个子块,然后各子块独立进行选择性映射(Selected Mappin,SLM),并将多个最佳相位序列的边带信息以纠错码的方式存放在一个块状导频之中,接收端使用最大似然准则来估计导频信号,解决了SLM边带信息传输和恢复问题,提高了频带利用率,并进行了仿真验证。互补累积概率为10-3时,导频辅助16QAM DCO-OFDM系统比原始DCO-OFDM提升了3 dB;误码率为10-4时,信噪比优2 dB。理论推导的PAPR互补累积分布函数表达式和仿真结果表明,本文所提方案的PAPR抑制性能提升,降低了限幅噪声对系统误码率的影响,纠错码提高了边带信息恢复的准确度,提高了系统的误码性能。In order to reduce the influence of high Peak to Average Power Ratio(PAPR) in DC-biased Optical OFDM(DCO-OFDM) system to the wireless optical communication.We propose a pilot-assisted PAPR reduction technique.The scheme divides multiple discrete frequency-domain signal sequences into subblocks before IFFT conversion,then every subblock choose the best phase sequences in SLM scheme independently,those side information is encoded to error-correcting code and stored in a block-type pilot,the maximum likelihood criterion is used to estimate the pilot signal at the receiver.It solves the problems of transportation and recovery of side information in the selected mapping scheme and improves bandwidth efficiency.And the consequences is verified through simulation.a pilot-assisted M-QAM DCO-OFDM system is capable of reducing the PAPR by over about 3 dB than the original DCO-OFDM at a modest complementary cumulative distribution function(CCDF) point of 10-3 for M=16,its SNR is superior 2 dB to the original scheme at the bit error rate of 10-4.The theoretical expression of function and the simulation show that the pilot-assisted PAPR reduction technique results in high reduction in PAPR and reduces the influence of limiting noise on BER.The error-correcting code ensures the accuracy of the side information,promoting the system performance.

关 键 词：峰均比 选择性映射 直流偏置光频分复用 导频 纠错码 

分 类 号：TN929.12[电子电信—通信与信息系统]