Visible LED communications in the dark?
Researchers at Dartmouth College, New Hampshire, working on a project called "˜DarkLight' have developed and demonstrated for the first-time, how visible light from LED lighting can be used to transmit data even when the light appears dark or off.
The study, "˜The DarkLight Rises: Visible Light Communication in the Dark' will be presented in New York at MobiCom 2016: The 22nd Annual International Conference on Mobile Computing and Networking on October 4th by Dartmouth co-author Zhao Tian, the lead PhD student for the project.
Through DarkLight, light-based communication is sustained even when LEDs emit extremely low luminance, by encoding data into ultra-short, imperceptible light pulses by using off-the-shelf, low-cost LEDs ($7 each) and photodiodes ($6-8 each).
The current DarkLight prototype supports 1.6kbps data rate at 1.8m distance.
"With DarkLight, we can potentially enable light sensing so that it is always on, 24/7, regardless of the light's illumination status," says the project's principal investigator Xia Zhou, assistant professor of computer science and co-director of the DartNets (Dartmouth Networking and Ubiquitous Systems Lab), which helped conduct the study. DartNets' research focuses on broad applications, systems, and networking perspectives of smartphones and smart device systems.
"DarkLight shows new possibilities on what visible light alone can do. We believe there are a lot more interesting applications yet to come," added Zhou.