CO-FBMC/OQAM系统导频辅助的时域相位噪声补偿  

Pilot-Based Time-Domain Phase Noise Compensation in CO-FBMC/OQAM System

作　　者：顾国民[1] 杨琛 卢瑾[1] 任宏亮[2] 吴斌琪 覃亚丽[2] 郭淑琴[2] 胡卫生[3] Gu Guomin;Yang Chen;Lu Jin;Ren Hongliang;Wu Binqi;Qin Yali;Guo Shuqin;Hu Weisheng(College of Computer Science and Technology,Zhejiang University of Technology,Hangzhou,Zhejiang 310023,China;College of Information and Engineering,Zhejiang University of Technology,Hangzhou,Zhejiang 310023,China;State Key Laboratory of Advanced Optical Communication Systems and Networks,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]浙江工业大学计算机科学与技术学院,浙江杭州310023 [2]浙江工业大学信息工程学院,浙江杭州310023 [3]上海交通大学区域光纤通信网与新型光通信系统国家重点实验室,上海200240

出　　处：《光学学报》2022年第4期23-37,共15页Acta Optica Sinica

基　　金：浙江省自然科学基金(LY20F050009);上海交通大学区域光纤通信网与新型光通信系统国家重点实验室开放基金(2020GZKF013);浙江省重点研发计划(2021C01117);2020年工业互联网创新发展工程项目(TC200H01V)。

摘　　要：针对相干光偏移正交调幅技术的多载波滤波器组传输(CO-FBMC/OQAM)系统,提出一种基于导频的时域相位噪声补偿算法。建立一个时域相位噪声补偿模型,即相位噪声用时域扩展的离散余弦变换(DCT)近似,相位噪声包括公共相位误差(CPE)和非CPE相位噪声,它们均可通过估计DCT系数来获得。为了计算这些DCT系数,先用基于导频的扩展卡尔曼滤波(EKF)估计CPE,然后将CPE补偿后一部分判决错误概率较高的数据舍弃,仅保留余下的CPE补偿后数据进行预判决用以预估发送端数据,最后在波特率为32 GBaud的背对背CO-FBMC/OQAM系统中对所提算法进行仿真验证。结果表明,对比一种改进的盲相位搜索(M-BPS)算法,所提算法仅有0.5%~2.0%的频谱效率下降。针对64阶QAM、子载波数M=256或512的系统,所提算法的线宽延迟乘积容忍度仍远大于M-BPS算法,但其复杂度仅为M-BPS算法的1/2。Aiming at the multi-carrier filter bank transmission system for coherent optical offset quadrature amplitude modulation(CO-FBMC/OQAM)technique,a pilot-based time-domain phase noise compensation algorithm is proposed.A time-domain phase noise compensation model is established,that is,phase noise is approximated by time-domain extended discrete cosine transform(DCT).Phase noise includes common phase error(CPE)and non-CPE phase noise,which can be obtained by estimating DCT coefficients.In order to calculate these DCT coefficients,the CPE is estimated by pilot-based extended Kalman filter(EKF).Then,some of the data with high error probability after CPE compensation are discarded,and only the remaining CPE compensation data are retained for pre-decision to predict the sender data.Finally,the proposed algorithm is simulated and verified in a back-to-back CO-FBMC/OQAM system with a baud rate of 32 GBaud.The results show that compared with an improved phase search(M-BPS)algorithm,the spectral efficiency of the proposed algorithm decreases by 0.5%--2.0%.For 64-order QAM systems with subcarriers M=256 or 512,the linewidth delay product tolerance of the proposed algorithm is still much larger than that of the M-BPS algorithm,but its complexity is only half that of the M-BPS algorithm.

关 键 词：光通信 相干光通信系统 偏移正交调幅技术的多载波滤波器组 基于导频的时域相位噪声补偿 载波间干扰 离散余弦变换 

分 类 号：TN913.7[电子电信—通信与信息系统]