NeTS: Small: RUI: Hybrid Visible-Light and Radio-Frequency Communications with Integrated Medium-Access Control

对无线通信需求的爆炸性增长导致了电磁频谱的拥挤。为了满足近期呈指数级增长的需求预测，需要考虑新技术和频段。其中一项技术是可见光通信(VLC)，其中基于发光二极管(LED)的照明系统可以在提供照明的同时传输数据。可见光光谱提供了非常大的电磁光谱带宽，有可能帮助缓解光谱紧缩。这项拟议的工作解决了将VLC通信与射频(RF)通信紧密集成的挑战，在射频通信中，只有在无法建立VLC链路时才使用RF信道，并解决了用户和接入点之间的上行数据传输的挑战，因为上行链路给VLC带来了许多挑战，包括移动设备上的高功率灯光会导致严重的眩光，以及高功耗。PI建议为混合VLC-RF通信系统开发实用、高效的协议和算法。PI在一个仅限本科生的机构工作，并将在这个项目中与本科生一起工作。此外，PI计划与一个青年教师计划合作，使用VLC作为示例技术，对初高中年龄的儿童进行数字通信基础知识的教育。该项目的成功完成将是使VLC-RF系统实用化的重要一步，这将有助于满足未来对无线数据通信日益增长的需求，并有助于培训下一代工程师。PI建议在硬件中设计、开发和实施具有集成介质访问控制(MAC)的RF-VLC混合系统，该系统还提供照明。该方案将涉及1)设计、仿真和实现VLC-RF MAC协议；2)开发物理层算法并将其集成到系统中，这些算法利用可以通过MAC协议交互获得的真实的信道信息；以及3)优化适用于室分复用(RDM)的MAC协议。所提出的系统将具有集成的MAC的事实，使得物理层实现与高层分离的实用VLC-RF系统成为可能，这是模块化通信系统设计的重要原则。针对RDM优化系统可能会显著提高数据速率，这是因为混合系统的支持VLC的下行链路具有更高的频谱重用。该项目的成功完成将有助于使VLC成为一个实用的模块化通信系统，从而改善互联网接入，特别是在人口稠密的城市环境中。

The explosion in demand for wireless communications has resulted in the crowding of the electromagnetic spectrum. To service the exponentially increasing demand forecast for the near future, new technologies and frequency bands need to be considered. One such technology is Visible-Light-Communications (VLC), where light-emitting diode (LED) based lighting systems can be used to transmit data while also providing illumination. The visible-light spectrum provides a very large bandwidth of electromagnetic spectrum that has the potential to help alleviate the spectral crunch. This proposed effort addresses the challenge of tightly integrating VLC communications with Radio-Frequency (RF) communications, where the RF channel is used only when a VLC link cannot be established, and for upstream data transmissions between users and access points since the upstream link poses a number of challenges for VLC including significant glare that would result from high-powered lights on mobile devices, and high power consumption. The PI proposes to develop practical, efficient protocols and algorithms for hybrid VLC-RF communications systems. The PI works in an undergraduate-only institution and will work with undergraduate students in this project. Additionally, the PI plans to work with a youth teacher program to educate middle- and high-school aged children on the fundamentals of digital communications, using VLC as an example technology. Successful completion of this project will be a major step towards making VLC-RF systems practical which will help service the increased demand for wireless data communications in the future, and help train the next generation of engineers. The PI proposes to design, develop, and implement in hardware, hybrid RF-VLC systems with integrated Medium-Access Control (MAC), which also provide illumination. The proposed program will involve 1) designing, simulating and implementing a VLC-RF MAC protocol; 2) developing and integrating into the system, physical layer algorithms that exploit channel information that can realistically be obtained through MAC protocol interactions; and 3) optimizing the MAC protocol for Room-Division Multiplexing (RDM). The fact that the proposed systems will have integrated MACs, enables practical VLC-RF systems for which physical layer implementation is decoupled from higher layers, which is an important principle of modular communications system designs. Optimizing the system for RDM can potentially increase data rates significantly due to the higher spectral re-use on the VLC enabled downlink of the hybrid system. Successful completion of this project will help make VLC a practical and modular communications system, which can lead to improved internet access, particularly in dense urban environments.