Scientists at Disney Research and the Swiss Federal Institute of Technology (Zurich) have created a visible light communications (VLC) networking technology that enables LED lights to communicate in a way that is compatible with Internet protocols. These advances, say the researchers, could allow VLC to play a significant role in the Internet of Things.
"Communication with light enables a true Internet of Things as consumer devices that are equipped with LEDs but not radio links could be transformed into interactive communication nodes," says Stefan Mangold, head of the wireless research group at Disney Research, Zurich. "We’re not just talking about sensors, smartphones and appliances. This easily could include toys that have LEDs, creating an Internet of Toys in which toys can be accessed, monitored and acted on remotely."
For their prototype realization, the researchers used commercial off-the-shelf LED bulbs modified to transmit and receive visible light signals. The modifications included an Atheros AR9331 SoC running the OpenWrt embedded Linux operating system, a VLC controller module, and an additional 3.3-V power supply for the SoC and controller.
The controller acts like an Ethernet interface, offering compatibility with Internet protocols such as TCP and UDP. The system was able to create networks that were able to communicate at up to 1 kbit/s. For more, see the paper "Linux Light Bulbs- Enabling Internet Protocol Connectivity for Light Bulb Networks-Paper" (PDF).