CRII: NeTS: Towards Ultra-High-Speed Mobile Visible Light Communication

Georgia State University Research Foundation, Inc., Atlanta GA

Investigators

Abstract

Radio frequency-based wireless communications plays a huge role in our modern society. However, the significant growth in the wireless data traffic has initiated the need for expanding the range of frequencies used for wireless communication. Visible Light Communication (VLC), where light is used as a medium for communication, has garnered significant attention over recent years due to its potential for ultra-high speeds. However, with rapid advancements in VLC, the communication speeds achieved so far are orders of magnitude less than its potential Terabits-per-second (Tbps) capacity. There is an urgent need for a breakthrough in VLC data speeds, and this project attempts to move toward it through a novel system architecture to support ultra-high data rates. The project will take advantage of industry meetings to disseminate outcomes and provides a variety of appealing educational activities involving high school and undergraduate students. This project makes an experimental VLC kit available to the community and makes the hardware, software implementation and data generated available to the public. Theoretical models estimate VLC information capacity to be of the order of Tbps, however, practical limitations in receiver designs have limited state-of-the-art VLC prototypes to data rates that are lower by orders of magnitude. To achieve high-speed reception, this project combines the fast sampling nature of photodiodes and the noise isolation property of imaging array structures into a unified structure that emulates a high-speed image sensing receiver. This project designs a novel VLC receiver architecture integrating a photodiode and an LCD array that acts as a pixelated shutter. Through this unified design, the receiver selects the exact area over which the transmitted signal is detected on the array, thus isolating actual light signal from ambient noise reaching the photodiode, resulting in a dramatic increase in the Signal to Noise Ratio (SNR). The signal isolation and SNR enhancement is enabled by the spatio-temporal mechanisms for selective signal reception and tracking on the LCD array. To achieve a larger field-of-view for reception, the receiver is fit with an 180-degree panoramic lens. This project develops a model to understand the relationship between spatial mobility and the light signal's location on the array and its strength and sets a baseline for designing signal tracking mechanisms to address mobility in high-speed VLC systems. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.