可见光通信预编码光正交频分复用系统的研究  

Research on Precoding Optical Orthogonal Frequency Division Multiplexing System in Visible Light Communication

作　　者：贾科军[1] 魏少博 蔺莹[1] 陈娟娟 曹明华[1] 黎锁平[2] Jia Kejun;Wei Shaobo;Lin Ying;Chen Juanjuan;Cao Minghua;Li Suoping(School of Computer and Communication,Lanzhou University of Technology,Lanzhou,Gansu 730050,China;School of Science,Lanzhou University of Technology,Lanzhou,Gansu 730050,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]兰州理工大学理学院,甘肃兰州730050

出　　处：《光学学报》2021年第17期49-56,共8页Acta Optica Sinica

基　　金：国家自然科学基金(61461026,61875080,61841107);甘肃省自然科学基金(18JR3RA153);兰州理工大学博士科研启动经费(061903)。

摘　　要：推导了预编码直流偏置光正交频分复用(DCO-OFDM)和预编码非对称限幅O-OFDM(ACO-OFDM)系统子载波信噪比(SNR)的表达式。仿真结果表明,在视线传播信道下,预编码不会影响系统的误码率(BER)性能;在多径信道下,预编码能均衡光无线信道的频率选择性衰落,使系统接收端子载波的SNR均匀化,从而改善系统的BER性能。此外,采用蒙特卡罗方法仿真分析了离散傅里叶变换、离散余弦变换和离散哈特莱变换预编码O-OFDM系统的峰均功率比(PAPR)和BER性能,验证了理论分析的正确性。最后,在考虑O-OFDM符号双边限幅的情况下,仿真验证了预编码对PAPR的抑制性能。Subcarrier signal-to-noise ratio(SNR)expressions are derived in this paper for the precoded direct current-biased optical orthogonal frequency division multiplexing(DCO-OFDM)system and the precoded asymmetrically clipped O-OFDM(ACO-OFDM)system.Simulation results show that in the line-of-sight channel,precoding does not affect the bit error rate(BER)performance of the systems.In the multipath channel,however,it can equalize the frequency-selective fading of the optical wireless channel,thereby uniformizing the subcarrier SNR at the receiving terminal of the O-OFDM system and ultimately improving the system BER performance.The Monte Carlo method is then used to simulate and analyze the peak-to-average power ratio(PAPR)and the BER of O-OFDM systems applying discrete Fourier transform precoding,discrete cosine transform precoding,and discrete Hartley transform precoding,which verifies the correctness of the theoretical analysis.The simulation also verifies the PAPR suppression function of precoding under bilateral clipping of O-OFDM signals.

关 键 词：光通信 预编码 光正交频分复用 峰均功率比 误码率 双边限幅 

分 类 号：TN929.12[电子电信—通信与信息系统]