Li-Fi, an alternative to Wi-Fi

Posted by Shweta Metkar on 18th November 2014, 12.08 PM

LiFi is a new way to establish wireless communication links using the Led lighting networks. Is an alternative to Wi–Fi that transmits data using the spectrum of visible light, has achieved a new breakthrough, with UK scientists reporting transmission speeds of 10Gbit/s – more than 250 times faster than 'superfast' broadband.

The term Li–Fi was coined by Edinburgh University's Prof Harald Haas during a TED talk in 2011 (see below for picture) though the technology is also known as visible light communications (VLC).

"My big idea is to turn light bulbs into broadband communication devices so that they not only provide illumination, but an essential utility"
Harald Haas, University of Edinburgh

Many experts claim that Li–Fi represents the future of mobile internet thanks to its reduced costs and greater efficiency compared to traditional Wi–Fi.

Both Wi–Fi and Li–Fi transmit data over the electromagnetic spectrum, but whereas Wi–Fi utilises radio waves, Li–Fi uses visible light. This is a distinct advantage in that the visible light is far more plentiful than the radio spectrum (10,000 times more in fact) and can achieve far greater data density.

The research was carried out by the Ultra Parallel Visible Light Communication Projects, a joint venture between the universities of Oxford, Cambridge, Edinburgh, St Andrews and Strathclyde, and FUNDED by the Engineering and Physical Sciences Research Council. Existing LED light bulbs could be converted to transmit Li–Fi signals with a single microchip, and the technology would also be of use in situations where radio frequencies cannot be used for fear of interfering with electronic circuitry.

The problem with Wi–Fi is that it uses radio signals and the amount of radio spectrum is limited. LiFi, however, could be deployed in everyday LED bulbs and cover the entire interior of a home or office. The system on show ran at 150 Mbps, but with a more powerful LED light, it could reach 3.5 Gbps.

Don't expect LiFi to be in your home or office any time soon. Researchers say it will take another five years before the technology is ready for commercialization.