Smart lighting—the use of highly energy-efficient and controllable solid-state light sources both to illuminate a defined space and facilitate optical wireless communication among electronic devices within that space—recently took a major step forward. In April Professor Thomas Little (ECE) began fabricating a new LED-based prototype that the National Science Foundation Smart Lighting Engineering Research Center at Boston University developed over the past year. Fulfilling an initial order for 40 units, Little is now shipping these devices to the Center’s industrial and educational outreach partners, a development that could spark new advances leading to commercialization.
“We now have a working system that’s robust enough to send to others to experiment with,” said Little, co-principal investigator and associate director of the NSF Smart Lighting Engineering Research Center, a program involving BU, Rensselaer Polytechnic Institute (RPI) and the University of New Mexico that facilitates research, industrial collaborations and educational initiatives aimed at advancing intelligent lighting systems and the development of transformative uses of light. “Our industrial partners and others can use this prototype as a reference design that they can adapt to develop a commercially viable system.”
Designed for indoor applications such as illuminating a room and transmitting data among laptops, printers, PDAs, thermostats and other devices, and outdoor use, such as leveraging headlights and brake lights to share road condition updates among multiple vehicles, LED-based smart lighting could deliver enhanced electronic communication capabilities at a reduced economic and environmental cost. Requiring far less energy than conventional lighting technologies, such as incandescent or compact fluorescent bulbs, and integrating multiple subsystems (unlike other ubiquitous communication platforms, such as Wi-Fi), Internet-controllable smart lights could perform tasks that range from programming illumination levels in a room to optimizing electric power distribution across a smart grid.
Much more compact, user-friendly and sophisticated than its predecessors, the current prototype, called Smart Light 1 (SL1), consists of a three-by-six-inch board comprised of two sections—one containing an array of nine high-brightness, white LEDs that transmit data to other transceivers, and the other with an array of three photodiodes that receive data. By keying the light on and off at a very high speed to create a pulsed signal, each SL1 board propagates data to laptops and other electronic devices, and is simply connected using a USB cable.
Toward a Commercial-Grade System
“The prototype demonstrates the viability of using modulated LED light at a useful data rate,” said Little. “The next step is to make the system completely self-contained, embedding all functionality within the bulb.” At that stage, each board will serve as an Internet and data communication access point for any electronic device within range, and thus enable multiple devices to communicate with one another.
While educational institutions such as RPI and high tech firms such as Interdigital and Booz Allen study the prototype and use it to spark further advances in smart lighting technology, Little and the BU team will continue to enhance the SL1’s capabilities and explore a number of potential smart lighting applications. These include high definition video streaming in high data-density scenarios such as aircraft seating in-flight entertainment, and improved vehicular safety via robust vehicle-to-vehicle communication.
Critical to commercial adoption of smart lighting is integration, miniaturization, and packaging with conventional lighting standards, and the achievement of higher data rates and lower integration costs, Little maintained.
“The goal is to enable any light to be a wireless optical access point, and to do this requires costs comparable to conventional lighting devices,” he said. “Future work in the Smart Lighting ERC will drive towards higher data rates and lower integration costs.”