基于正交频分复用的室内可见光定位理论与关键技术研究

The indoor positioning based on visible light communication has great development potential and application prospect, due to the advantages of high energy efficiency, green environmental protection, no electromagnetic interference, and both lighting and positioning function, etc. This project proposes a visible light positioning (VLP) scheme based on orthogonal frequency division multiplexing (OFDM) to meet the requirement of high reliable communication, high accuracy positioning and optical signal interference elimination for indoor VLP system. Compared with the existing VLP system based on single carrier modulation, the OFDM-VLP achieves high spectral efficiency and high-speed transmission easily, has rich and flexible access mode and bandwidth allocation, and combats the linear transmission impairments of wireless optical channel and multipath effects effectively. In addition, the orthogonal frequency division multiple access mode can eliminate the adjacent optical signal interference easily. The project is to focus on some scientific problems for OFDM-VLP, such as the adjacent optical signal interference and suppression, wireless optical channel model and capacity, and low complexity, high accuracy and high robustness of positioning algorithm. The researchers aim to demonstrate an OFDM-based visible light communication and positioning system which support high reliable transmission and high accuracy positioning, thus to provide theoretical and technical support for the development and application of visible light communication.

基于可见光通信的室内定位技术由于能效高，绿色环保，不受电磁干扰影响，兼具照明和定位两种功能等优势，被认为是极具发展潜力和应用前景的技术。本项目针对室内可见光定位高可靠通信、高精度定位、抗光干扰等需求，提出了基于正交频分复用的可见光定位方案。相比于现有单载波调制的可见光定位系统，正交频分复用可见光定位系统易于实现高谱效、高速的传输，其多址接入方式与带宽资源的分配方式更加丰富灵活，且能够有效地抵抗无线光信道中线性的传输损伤与多径效应。此外，采用正交频分多址的方式易于消除相邻光信号的干扰。本项目重点研究可见光信号干扰与抑制，精密的可见光信道模型与传输容量表达，以及低复杂度、高精度、高健壮性的定位算法，最终搭建正交频分复用可见光通信与定位演示系统，支持高可靠通信，高精度定位，为可见光通信的应用与发展提供理论与技术支撑。

可见光通信作为一种新兴无线通信方式，因其能效高，绿色环保，不受电磁干扰影响，兼具照明、通信与定位等多种功能等优势而成为近年来的一个研究热点。针对室内可见光定位系统高可靠通信、高精度定位、抗可见光干扰等需求，本项目提出了基于正交频分复用的技术解决方案。主要的创新工作包括：（1）设计了正交频分多址的网络架构，有效抑制可见光干扰。提出了基于照相机接收的可见光通信方式，其可有效实现多个可见光信号的分离，避免了相邻可见光信号干扰。（2）提出了非正交多址可见光通信方法并完成了原型样机的研制，其可极大提升可见光通信系统容量、可支持用户数、用户公平性。（3）分别提出了基于正交频分多址，基于照相机接收以及基于神经网络的可见光定位方法，并完成了原型样机的研制。实验结果表明，所提出的可见光定位系统，可实现无误码传输，定位误差均小于0.1m。其在地下车库、机器人室内定位、大型商场、会场等场所具有广泛的应用前景。