Researchers achieve 10Gbit/s Li-Fi data transmission record

London: In a breakthrough, UK scientists have achieved record data transmission speeds of 10 gigabits per second - more than 250 times faster than `superfast` broadband - using LED light bulbs.

The researchers used a micro-LED light bulb to transmit 3.5Gbit/s via each of the three primary colours - red, green, blue - that make up white light. The research, known as the ultra-parallel visible light communications project, is a joint venture between the universities of Edinburgh, St Andrews, Strathclyde, Oxford, and Cambridge. The tiny micro-LED bulbs, developed by the University of Strathclyde, Glasgow, allow streams of light to be beamed in parallel, each multiplying the amount of data that can be transmitted at any one time. Using a digital modulation technique called Orthogonal Frequency Divisional Multiplexing (OFDM), researchers enabled micro-LED light bulbs to handle millions of changes in light intensity per second, effectively behaving like an extremely fast on/off switch. This allows large chunks of binary data - a series of ones and zeros - to be transmitted at high speed. Earlier this month, Chinese scientists developed a microchipped LED bulb that can produce data speeds of up to 150 megabits per second (Mbps), with one bulb providing internet connectivity for four computers. And earlier this year, Germany`s Fraunhofer Heinrich Hertz Institute claimed that data rates of up to 1Gbit/s per LED light frequency were possible in laboratory conditions. Professor Harald Haas, an expert in optical wireless communications at the University of Edinburgh and one of the project leaders has coined the term "light fidelity" or Li-Fi - also known as visual light communications (VLC). In 2011, Haas demonstrated how an LED bulb equipped with signal processing technology could stream a high-definition video to a computer. Li-fi promises to be cheaper and more energy-efficient than existing wireless radio systems. Another advantage, Haas argues, is that evenly spaced LED transmitters could provide much more localised and consistent internet connectivity throughout buildings.