可见光通信具有不受电磁干扰、绿色节能等优点，可以为无线电禁止区域和无线电屏蔽区域，提供安全高效的照明和通信。然而目前大多数室内可见光通信系统的研究，都忽略了照明需求和大范围通信需求。因此，本文将照明通信一体化作为研究的基点，在满足照明需求的同时，实现大范围通信，设计的系统具有实用性。针对可见光通信系统中，光源难以用于照明、通信范围小和系统结构复杂的问题，提出了相应的算法和解决方案，并在工程实现过程中验证了技术方案的可行性。首先，本文介绍了照明光通信研究基础。阐述了LED的发光原理和特性，重点分析了照明与通信之间的折衷关系。介绍了LED驱动电路特点，以及照明光通信系统的构成。然后，本文实现了一个基于照明LED的移动通信定位系统。针对通信范围小、难以支持移动通信定位的问题，提出了一种基于室内照明LED的OCC定位算法，用于解决移动定位时的具体问题。设计了LED定位信号的传输和移动时的接收方案，并实现了一个照明、移动通信定位一体化的系统，测试结果表明，该系统可以支持1.2m/s移动时的亚米级精度定位。最后，本文实现了一个基于照明LED的Li-Fi系统。针对系统电路结构复杂的问题，提出了一种适用于照明光通信系统的数字滤波算法，代替硬件电路的功能。通过对接收信号的分解，调整滤波器参数，简化滤波后最佳门限的计算公式，代替了滤波电路和自动增益控制电路的设计。同时，对滤波后的过采样信号，将采样时刻同步到信噪比最高的时刻，消除定时误差，代替了时钟同步电路的功能。最终实现了10Mbit/s实时下行传输速率，LED的功率大于40W，下行传输距离大于2m，可靠通信的范围约4.5m2。
Visible light communication (VLC) possesses advantages such as immunity to electromagnetic interference and green energy, making it a promising solution for providing secure and efficient illumination and communication in radio-restricted and radio-shielded areas. However, most current research on indoor VLC systems neglects the requirements of both illumination and wide-ranging communication. Therefore, this thesis takes the integration of illumination and communication as the research focal point, aiming to design a practical system that fulfills illumination needs while enabling wide-ranging communication. In response to challenges in VLC systems, including the limitations of using light sources for illumination, restricted communication range, and complex system structures, corresponding algorithms and solutions are proposed. The feasibility of these technical approaches is validated through the engineering implementation process.Firstly, the thesis introduces the foundation of illumination-based VLC research. It elucidates the luminescence principles and characteristics of LED emission, with a particular focus on the trade-off relationship between illumination and communication. LED driver circuit features and the composition of illumination-based VLC systems are also presented.Subsequently, the thesis implements a mobile communication positioning system based on illumination LEDs. To address the issues of limited communication range and difficulties in supporting mobile communication positioning, an indoor positioning algorithm based on illumination LEDs, referred to as the Optical Camera Communication (OCC) positioning algorithm, is proposed to tackle specific challenges during mobile positioning. The transmission of LED positioning signals and the receiving scheme during movement are designed, resulting in an integrated system that combines illumination, mobile communication, and positioning. Test results demonstrate that the system can achieve sub-meter accuracy for positioning at a mobile speed of 1.2 m/s.Lastly, the thesis realizes a Li-Fi system based on illumination LEDs. To overcome the complexity of system circuit structures, a digital filtering algorithm for illumination-based VLC systems is proposed as a substitute for hardware circuit functionality. By decomposing the received signal, adjusting filter parameters, and simplifying the calculation formula for the optimal threshold after filtering, the design of filter circuits and automatic gain control circuits is replaced. Additionally, for oversampled signals after filtering, sampling moments are synchronized to the highest signal-to-noise ratio moment, eliminating timing errors and replacing clock synchronization circuits. Ultimately, a real-time downlink transmission rate of 10 Mbit/s, LED power exceeding 40W, a downlink transmission distance greater than 2m, and a reliable communication coverage area of approximately 4.5m2 are achieved.
