基于OFDM的室内光无线传输技术研究
发布时间：2019-02-11 16:06
【摘要】：可见光通信(VLC)系统是室内高速数据传输极具吸引力和竞争力的解决方案。为满足室内可见光通信高速数据传输的需求,在可见光通信系统中引入正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)技术。由于VLC系统采用强度调制／直接检测(IM/DD)技术,调制LED灯强度的OFDM符号必须满足实数、正极性的要求,因此本文对可见光OFDM信号单极化方法的原理做了详细的研究,主要有加直流偏置光OFDM (DC Biased Optical OFDM, DCO-OFDM)、非对称性限幅光OFDM (Asymmetrically Clipped Optical OFDM, ACO-OFDM)、单极性光OFDM (Unipolar OFDM,U-OFDM)、改进的ACO-OFDM (Modified ACO-OFDM, MACO-OFDM)和翻转OFDM (Flip-OFDM),并从功率效率、频带利用率及误码性能等方面对几种可见光OFDM系统做对比分析。 作为未来短距离无线通信有效可选方案的可见光通信,照明控制是其面临的主要挑战之一。如何在保证可靠的宽带通信链路的同时满足高质量的照明状态是可见光通信的重要课题。本文在分析了采用连续电流调节(CCR)和脉冲宽度调制(PWM)两种调光控制技术的光OFDM系统工作原理的基础上,提出了一种新的室内可见光高速通信调光控制系统设计方案。该方案将照明应用中的两种调光技术引入到功率效率高、误码性能好的Unipolar OFDM系统中,在提供良好传输性能的同时实现了照明信号的连续调节和线性调节功能。仿真结果表明,本文提出的U-OFDM调光控制系统可在不牺牲照明质量的同时获得更好的误码性能,对于设计具有调光控制功能的室内VLC高速数据通信系统,基于U-OFDM的PWM调光控制是一种最佳的解决方法。此外,针对室内低照明、低功耗的应用需求,本文提出了一种功率更加有效的ZACO-OFDM (Zero-padding ACO-OFDM)系统,仿真分析表明,ZACO-OFDM系统可在不损失误码性能的情况下提高系统的功率效率、调光深度及灵活性。
[Abstract]:Visible light communication (VLC) system is an attractive and competitive solution for indoor high-speed data transmission. In order to meet the demand of high speed data transmission for indoor visible light communication, orthogonal frequency division multiplexing (Orthogonal Frequency Division Multiplexing,OFDM) technology is introduced in the visible light communication system. Because the intensity modulation / direct detection (IM/DD) technique is adopted in VLC system, the OFDM symbol of the intensity modulation of LED lamp must meet the requirements of real number and positive pole, so the principle of single polarization method of visible light OFDM signal is studied in detail in this paper. The main ones are DC bias light (OFDM (DC Biased Optical OFDM, DCO-OFDM), asymmetric limiting light (OFDM (Asymmetrically Clipped Optical OFDM, ACO-OFDM), unipolar light (OFDM (Unipolar OFDM,U-OFDM), and improved ACO-OFDM (Modified ACO-OFDM,). MACO-OFDM) and flip OFDM (Flip-OFDM). Several visible light OFDM systems are compared and analyzed from the aspects of power efficiency, band efficiency and bit error performance. As an effective alternative for short range wireless communication in the future, lighting control is one of the main challenges. How to ensure reliable broadband communication links and meet the high quality of lighting is an important subject of visible light communication. Based on the analysis of the working principle of the optical OFDM system which adopts two dimming control technologies: continuous current regulation (CCR) and pulse width modulation (PWM), a new design scheme of the indoor visible light high speed communication dimming control system is proposed. In this scheme, two dimming techniques in lighting applications are introduced into Unipolar OFDM systems with high power efficiency and good bit error performance, which can provide good transmission performance and realize the continuous and linear adjustment functions of lighting signals at the same time. The simulation results show that the proposed U-OFDM dimming control system can achieve better bit error performance without sacrificing lighting quality. For the design of indoor VLC high-speed data communication system with dimming control function, PWM dimming control based on U-OFDM is the best solution. In addition, a more efficient ZACO-OFDM (Zero-padding ACO-OFDM) system is proposed to meet the requirements of indoor low lighting and low power consumption. The simulation results show that, ZACO-OFDM system can improve power efficiency, dimming depth and flexibility without losing bit error performance.
【学位授予单位】：大连海事大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN929.1
本文编号：2419887
[Abstract]:Visible light communication (VLC) system is an attractive and competitive solution for indoor high-speed data transmission. In order to meet the demand of high speed data transmission for indoor visible light communication, orthogonal frequency division multiplexing (Orthogonal Frequency Division Multiplexing,OFDM) technology is introduced in the visible light communication system. Because the intensity modulation / direct detection (IM/DD) technique is adopted in VLC system, the OFDM symbol of the intensity modulation of LED lamp must meet the requirements of real number and positive pole, so the principle of single polarization method of visible light OFDM signal is studied in detail in this paper. The main ones are DC bias light (OFDM (DC Biased Optical OFDM, DCO-OFDM), asymmetric limiting light (OFDM (Asymmetrically Clipped Optical OFDM, ACO-OFDM), unipolar light (OFDM (Unipolar OFDM,U-OFDM), and improved ACO-OFDM (Modified ACO-OFDM,). MACO-OFDM) and flip OFDM (Flip-OFDM). Several visible light OFDM systems are compared and analyzed from the aspects of power efficiency, band efficiency and bit error performance. As an effective alternative for short range wireless communication in the future, lighting control is one of the main challenges. How to ensure reliable broadband communication links and meet the high quality of lighting is an important subject of visible light communication. Based on the analysis of the working principle of the optical OFDM system which adopts two dimming control technologies: continuous current regulation (CCR) and pulse width modulation (PWM), a new design scheme of the indoor visible light high speed communication dimming control system is proposed. In this scheme, two dimming techniques in lighting applications are introduced into Unipolar OFDM systems with high power efficiency and good bit error performance, which can provide good transmission performance and realize the continuous and linear adjustment functions of lighting signals at the same time. The simulation results show that the proposed U-OFDM dimming control system can achieve better bit error performance without sacrificing lighting quality. For the design of indoor VLC high-speed data communication system with dimming control function, PWM dimming control based on U-OFDM is the best solution. In addition, a more efficient ZACO-OFDM (Zero-padding ACO-OFDM) system is proposed to meet the requirements of indoor low lighting and low power consumption. The simulation results show that, ZACO-OFDM system can improve power efficiency, dimming depth and flexibility without losing bit error performance.
【学位授予单位】：大连海事大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN929.1
【参考文献】
相关期刊论文 前1条
1 丁德强;柯熙政;;可见光通信及其关键技术研究[J];半导体光电;2006年02期
，本文编号：2419887
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