可见光通信调制技术与MIMO研究
发布时间：2018-11-08 16:26
【摘要】：可见光通信(Visible Light Communication，VLC)是利用LED发出的肉眼察觉不到的高速调制信号来实现信息传输的通信技术。可见光通信兼顾照明和通信，具有网络布置方便、无电磁干扰、通信带宽大等优点，有着巨大的发展潜力。本论文围绕室内可见光通信存在的技术难点开展了具体的研究工作，包括点对点通信中LED编码、通信的调制、MIMO复用结构等。 首先，论文介绍了可见光通信系统的组成；搭建了一套白光LED音频传输的实验平台，实现了室内短距离可见光音频传输，实验中暴露出可见光通信在未有纠错编码的情况下性能较差的问题。因此，本论文提出了适合可见光传输且具备调光功能的M-PAM和RS（15,11）编码方式，并对其性能作了进一步分析。结论表明RS（15,11）纠错编码在SNR4dB时，误码率明显改善，且当SNR≥10dB后，误比特率将低于10-4；相比于未使用RS编码的4-PAM信号的误比特率性能，RS（15,11）编码具有2dB的性能改善。 其次，研究了可见光DCO-OFDM调制，并计算不同M、DCdB对DCO-OFDM误码率的影响，，研究发现4QAM-DCO-OFDM的性能最优，当DCdB=0、SNR8dB时误码率可降低到10-5；当DCdB=1、SNR12dB时误码率为10-5。此外，建立室内可见光通信系统模型，获取多径反射后脉冲时延及衰减的幅频响应，仿真DCO-OFDM信号在一次反射路径下的误码率性能。仿真结果表明，多径干扰对误码率影响甚重，无论M、DCdB为多少，系统的误码率都大于10-3。本论文研究成果为改进DCO-OFDM调制提供了理论依据。最后，介绍了可见光通信MIMO复用系统原理，研究了MIMO复用系统的光学结构如光源发散角、偏移角及不同波长的光波与收发光学天线（透镜）尺寸的对通信性能的影响，为优化阵列尺寸与传输距离提供了理论参数；并提出了一种QR码图形LEDs空间MIMO阵列发送，实现了通信距离5米，通信速率24Kbps的单工通信，验证了可见光MIMO复用结构的可行性，为可见光通信提供了实验参考。
[Abstract]:Visible light communication (Visible Light Communication,VLC) is a kind of communication technology which can realize the information transmission by using the high speed modulation signal that LED can't detect. Visible light communication has many advantages, such as convenient network arrangement, no electromagnetic interference and large communication bandwidth, so it has great development potential. This paper focuses on the technical difficulties of indoor visible light communication, including LED coding, modulation and MIMO multiplexing in point-to-point communication. Firstly, the composition of visible light communication system is introduced. A set of white light LED audio transmission experiment platform is set up to realize indoor short distance visible light audio transmission. In the experiment, the performance of visible light communication is poor without error correcting coding. Therefore, in this paper, the M-PAM and RS (15F11) coding scheme, which is suitable for visible light transmission and has dimming function, is proposed, and its performance is further analyzed. The results show that the error rate of RS (15M11) error-correcting code is significantly improved when SNR4dB is used, and when SNR 鈮
本文编号：2319033
[Abstract]:Visible light communication (Visible Light Communication,VLC) is a kind of communication technology which can realize the information transmission by using the high speed modulation signal that LED can't detect. Visible light communication has many advantages, such as convenient network arrangement, no electromagnetic interference and large communication bandwidth, so it has great development potential. This paper focuses on the technical difficulties of indoor visible light communication, including LED coding, modulation and MIMO multiplexing in point-to-point communication. Firstly, the composition of visible light communication system is introduced. A set of white light LED audio transmission experiment platform is set up to realize indoor short distance visible light audio transmission. In the experiment, the performance of visible light communication is poor without error correcting coding. Therefore, in this paper, the M-PAM and RS (15F11) coding scheme, which is suitable for visible light transmission and has dimming function, is proposed, and its performance is further analyzed. The results show that the error rate of RS (15M11) error-correcting code is significantly improved when SNR4dB is used, and when SNR 鈮
本文编号：2319033
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