自适应调制STBC-OCT预编码在MIMO-OFDM VLC系统中的研究  

Research of adaptive modulation STBC-OCT precoding in MIMO-OFDM VLC system

作　　者：张娜 柯熙政[2] 袁训锋 李丽君 Zhang Na;Ke Xizheng;Yuan Xunfeng;Li Lijun(Electronic Information and Electrical Engineering College,angluo University,726000,China;School of Automation and Information,Xi'an University of Technology,Xi'an 710048,China)

机构地区：[1]商洛学院电子信息与电气工程学院,河南商洛726000 [2]西安理工大学自动化与信息工程学院,陕西西安710048

出　　处：《红外与激光工程》2022年第6期428-435,共8页Infrared and Laser Engineering

基　　金：陕西省教育厅专项项目(19JK0253);商洛市科技局项目(SK2018-21);商洛学院科研项目(21FK004)。

摘　　要：为改善多入多出正交频分复用(MIMO-OFDM)的可见光通信(VLC)系统的性能,提出将自适应调制、空时分组码(STBC)及正交循环矩阵变换(OCT)相结合应用于该系统中,设计并建立了一个2×2 MIMO-OFDM系统,来评估所提出的自适应调制STBC-OCT预编码方案的性能。在不同的调制方式、不同的编码方案下研究其误码率(BER)性能、峰均功率比(PAPR)性能、不同的直流偏置(DC)与驱动电压峰值(V-(PP))下的BER性能。结果表明:与其它预编码方法相比,采用自适应调制STBC-OCT预编码方案能获得相对均衡且高的信噪比(SNR)值及更低的PAPR。当传输距离为0.5 m,DC为2.7 V、V-(PP)为2.7~2.8 V时所提方案能获得最佳的BER性能,并始终低于前向纠错(preFEC)门限7%的阈值3.8×10^(-3).该方案能够有效地克服MIMO-OFDM VLC系统带宽限制的问题并提供最佳的可靠性。An efficient precoding scheme combing adaptive modulation,space-time block code (STBC) and orthogonal circulant matrix transform (OCT) is proposed to improve the performance of multiple input-multiple output-orthogonal frequency division multiplexing (MIMO-OFDM) based visible light communication (VLC)systems in this work.A 2×2 MIMO-OFDM VLC system is designed and established to evaluate the performance of the proposed adaptive modulation STBC-OCT precoding scheme.The performances of bit error rate (BER),peak-to-average power ratio (PAPR) are investigated experimentally for different modulation and coding schemes.The performances of BER are studied in different direct current bias (DC) and driving peak-to-peak voltages (V-(PP)) offsets.The experimental results show that the system using proposed adaptive modulated STBC-OCT precoding obtains a relatively flat and higher signal-to-noise ratio (SNR) values,lower PAPR compared with other precoding methods.The proposed scheme can obtain the best BER performance,and it is always lower than the 7%pre-forward error correction (pre-FEC) threshold of 3.8×10^(-3) with the transmission distance is 0.5 m,DC is set to 2.7 V and VPis 2.7-2.8 V,it can effectively overcome the bandwidth limitation of MIMO-OFDM VLC system and provide the best reliability.

关 键 词：可见光通信 多入多出-正交频分复用 空时分组码 正交循环矩阵变换 自适应调制 

分 类 号：TN929.12[电子电信—通信与信息系统]