室内MIMO-VLC系统光源布局研究
发布时间：2018-08-25 07:45
【摘要】：在能源日益紧缺、环境问题日益凸显的今天,由于具有亮度高、能耗低、寿命长、性能稳定等诸多优点,白光LED越来越广泛地应用于生活与商业照明。室内可见光通信(Visible Light Communication,VLC)以白光LED为光源,既能提供很好的照明,又能实现稳定可靠的数据通信。但是,LED调制带宽低的特性限制了VLC的系统容量和数据的高速率传输,而结合多输入多输出(Multi-input Multi-output,MIMO)技术的VLC系统在收发终端均采用多天线单元,创造并行的无线传输信道,在没有加大发射功率和系统带宽的前提之下,大量提升通信质量和传输速度。在研究MIMO-VLC系统时,我们首先面对的是其光源布局问题。合理的布局不仅是系统正常工作的必要条件,并且可以花最小的代价解决一些实际问题。例如,MIMO-VLC系统利用信号的多径传播提高系统容量和传输速率,但是由于漫反射链路的存在,系统会存在码间干扰(Inter Symbol Interference,ISI),导致误码率升高。不同的光源布局会呈现一个不同的反射功率分布,如何选择一个反射功率分布对系统性能影响最小的光源布局成为本领域的一个研究热点。由于MIMO-VLC系统在设计光源布局时其设计方法和需考虑的关键因素与普通的VLC系统有所不同。因此,本文首先分析了VLC系统模型,其次在考虑漫反射链路的情况下分析了结合有MIMO技术的VLC系统模型,并提出了其设计布局的关键要素:(1)满足系统基本通信/照明条件;(2)尽可能使漫反射对系统性能影响微弱。最后,通过仿真实现搜寻保证系统正常运行的阵列布局可行区域,并借助遗传算法(Genetic Algorithms,GA)在可行区域内进行布局优化,使得码间干扰尽可能小地影响系统性能,并仿真了优化前后的接收面误码率分布情况。
[Abstract]:With the increasing shortage of energy and environmental problems, white LED is more and more widely used in daily and commercial lighting due to its advantages such as high brightness, low energy consumption, long life, stable performance and so on. Indoor visible light communication (Visible Light Communication,VLC) uses white light LED as light source, which can not only provide good lighting, but also realize stable and reliable data communication. However, the low modulation bandwidth of VLC limits the system capacity and the high rate of data transmission. The VLC system combined with multi-input and multi-output (Multi-input Multi-output,MIMO) technology uses multi-antenna units to create parallel wireless transmission channels at transceiver terminals. Without increasing transmission power and system bandwidth, the communication quality and transmission speed are greatly improved. In the study of MIMO-VLC system, we first face the problem of light source layout. Reasonable layout is not only a necessary condition for the normal operation of the system, but also can solve some practical problems at the lowest cost. For example, in MIMO-VLC system, multipath propagation is used to improve the system capacity and transmission rate. However, due to the existence of diffuse reflection link, the system will have inter-symbol interference (Inter Symbol Interference,ISI), which leads to the increase of bit error rate (BER). Different light source configurations will present a different reflected power distribution. How to select a light source layout which has the least effect on system performance has become a research hotspot in this field. The design method and key factors of MIMO-VLC system are different from those of ordinary VLC system. Therefore, this paper first analyzes the VLC system model, and then analyzes the VLC system model with MIMO technology in consideration of diffuse reflection link. The key elements of its design and layout are proposed as follows: (1) satisfying the basic communication / lighting conditions of the system; (2) making diffuse reflection have a weak effect on the performance of the system as much as possible. Finally, the feasible area of array layout is searched by simulation, and the layout is optimized within the feasible area by genetic algorithm (Genetic Algorithms,GA), which makes the inter-symbol interference (ISI) affect the system performance as little as possible. The BER distribution of the receiver before and after the optimization is simulated.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN929.1
本文编号：2202228
[Abstract]:With the increasing shortage of energy and environmental problems, white LED is more and more widely used in daily and commercial lighting due to its advantages such as high brightness, low energy consumption, long life, stable performance and so on. Indoor visible light communication (Visible Light Communication,VLC) uses white light LED as light source, which can not only provide good lighting, but also realize stable and reliable data communication. However, the low modulation bandwidth of VLC limits the system capacity and the high rate of data transmission. The VLC system combined with multi-input and multi-output (Multi-input Multi-output,MIMO) technology uses multi-antenna units to create parallel wireless transmission channels at transceiver terminals. Without increasing transmission power and system bandwidth, the communication quality and transmission speed are greatly improved. In the study of MIMO-VLC system, we first face the problem of light source layout. Reasonable layout is not only a necessary condition for the normal operation of the system, but also can solve some practical problems at the lowest cost. For example, in MIMO-VLC system, multipath propagation is used to improve the system capacity and transmission rate. However, due to the existence of diffuse reflection link, the system will have inter-symbol interference (Inter Symbol Interference,ISI), which leads to the increase of bit error rate (BER). Different light source configurations will present a different reflected power distribution. How to select a light source layout which has the least effect on system performance has become a research hotspot in this field. The design method and key factors of MIMO-VLC system are different from those of ordinary VLC system. Therefore, this paper first analyzes the VLC system model, and then analyzes the VLC system model with MIMO technology in consideration of diffuse reflection link. The key elements of its design and layout are proposed as follows: (1) satisfying the basic communication / lighting conditions of the system; (2) making diffuse reflection have a weak effect on the performance of the system as much as possible. Finally, the feasible area of array layout is searched by simulation, and the layout is optimized within the feasible area by genetic algorithm (Genetic Algorithms,GA), which makes the inter-symbol interference (ISI) affect the system performance as little as possible. The BER distribution of the receiver before and after the optimization is simulated.
【学位授予单位】：西安电子科技大学
【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 赵婷;李洪祚;宫玉琳;;可见光通信中高阶调制格式研究[J];长春理工大学学报(自然科学版);2013年05期
，本文编号：2202228
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