Multifunctional Polymer Light-Emitting Diodes with Visible Light Communications (MARVEL)

随着电信网络承载的通信量的急剧增加，对无线资源（频谱）的需求正在迅速超过其有限的供应。在高密度用户场景下，由于用户需求导致接入受限，频谱拥塞导致的业务质量严重下降日益明显。这个问题在室内应用中更加严重，因为缺乏频谱和大量用户会导致显著的网络减速。据估计，超过70%的无线通信发生在室内环境（家庭/办公室等）。因此，需要可靠、低成本、高容量的无线技术来确保始终无缝的室内无线连接。可见光通信（VLC）使用可见频段（~400 THz）提供无线连接，这是一个具有高安全性的免许可频谱，其光源用于提供照明。VLC利用半导体发光二极管（LED），可以高速调制，同时提供恒定的照明水平。传统上，vlc使用无机led作为其发射机的光源。这类器件引入了尚未解决的重大缺陷，例如由于易碎且复杂的外延加工方法昂贵而无法生产大型面板。此外，为了提供适当的照明，需要器件矩阵，从而引入了显着的电路复杂性。其他缺点包括无法使用对移动设备有吸引力的柔性基板，以及难以生产具有固有不同波长的设备。所有这些缺点都可以通过用有机聚合物代替常用的无机金属作为led的半导体材料来解决。聚合物led （led）可以在室温下使用廉价的湿式加工方法（如喷墨打印）制造，以极低的成本生产具有大光活性区域的单面板设备。此外，led可以沉积在各种各样的衬底材料上，具有不同的形状，从而可以开发新一代设备。使用简单的制造工艺（一步沉积不同的有机聚合物），led可以设计成产生红、绿、蓝（RGB）光，然后组合起来，从而实现照明和信号传输的双重功能。在过去的十年中，申请这项资助的团队共同展示了在VLC系统中使用有机（聚合物）led的重大成功，具有制造，成本和运营优势。我们之前的工作在传输信号质量和比特率方面创造了几个“世界第一”，我们的研究结果发表在主要的国际期刊和会议上。在这个提案中，我们将以现有的优势和我们三个团队联盟的各种专业知识为基础。特别是我们在无机半导体，光学元件设计和制造，电子电路设计和通信系统集成方面的研究，将用于构建和演示一个新的基于PLED的VLC概念验证系统，其中包括新的器件，电路和系统设计。我们期望在真实的室内环境中实现前所未有的VLC传输速度。该项目将研究设计led的新方法和新的光学技术，以最大限度地提高其光效。将研究新的电路和通信工程技术，以优化电子电路与led的耦合，克服一些led固有的数据承载限制。我们的目标是组装一个完整的系统，并在专门设计的VLC测试室中进行测试。总之，我们认为这项工作非常及时，因为它解决了两个关键挑战；系统的设计工作在免许可的频谱带和提供易于制造和低成本的有机光电器件。

With the dramatic increase in traffic carried by telecommunication networks, the demand for wireless resources (spectrum) is quickly outstripping its limited supply. Serious deterioration of service quality due to spectral congestion is becoming evident in high-density user scenarios, where users demand leads to a limited access. This problem is even worse in indoor applications where a lack of spectrum and a large number of users causes significant network slowdown. It is estimated that more than 70% of wireless traffic takes place in an indoor environment (home/office etc.). Thus, there is the need for reliable low-cost, high-capacity wireless technologies to ensure seamless indoor wireless connectivity at all times. Visible light communications (VLC) offers wireless connectivity using the visible band (~400 THz), which is a license free spectrum with high security and where its sources are used to provide lighting. VLC utilises semiconductor light emitting diodes (LED), which can be modulated at high speeds while providing a constant level of illumination. Traditionally, VLCs use inorganic LEDs as their transmitters' light sources. Such devices introduce significant drawbacks that have yet to be addressed, such as the inability to produce large panels due to the brittle and complex epitaxial processing methods that are expensive. Furthermore, to provide proper illumination, matrices of devices are required, thus introducing a significant circuit complexity. Other drawbacks include the inability to use flexible substrates that are attractive for mobile devices and the difficulties in producing devices with inherent different wavelengths. All of these disadvantages can be dealt with by replacing the commonly used inorganic metals by organic polymers as the semiconductor material of the LEDs. Polymer LEDs (PLEDs) can be manufactured using inexpensive wet processing methods at room temperature (such as inkjet printing) to produce single panel devices with large photoactive areas, at extremely low cost. Further, PLEDs can be deposited on a wide variety of substrate materials and with different shapes, allowing the development of a new generation of devices. Using a simple manufacturing process (one step deposition of different organic polymers) PLEDs may be designed to produce red, green and blue (RGB) light and then combined to allow the dual function of lighting and signal transmission.Over the past decade, the teams applying for this grant have collectively demonstrated major successes in using organic (polymer) LEDs in VLC systems, with manufacturing, cost and operational advantages. Our previous work has led to several "world firsts" in terms of transmitted signal quality and bit rates, and our results were published at leading international journals and conferences. In this proposal we will build on the existing strengths and varied expertise of our three team consortium. Specifically our research in inorganic semiconductors, optical component design and fabrication, electronic circuit design and communication systems integration, will be used to construct and demonstrate a new PLED based VLC proof of concept system, which includes novel device, circuit and system designs. We expect to achieve unprecedented VLC transmission speeds in realistic indoor environments. The project will study new methods of designing PLEDs and new optical techniques to maximise their light efficiency. New circuits and communication engineering techniques will be investigated to allow optimised coupling of electronic circuitry to PLEDs, overcoming some of PLEDs inherent data carrying limitations. We aim to assemble a complete system and test in in a specially designed test chambers of VLC.In summary, we believe this work to be highly timely as it addresses the two key challenges; the design of systems operating in license free spectral bands and the provision of easy to manufacture and low cost organic optoelectronic devices.