Monday, 4 November 2013
LED Lights Show Promise for High-Speed Data Transmission
There's no doubt that LED lights are the latest craze for everything from household to decorative to automotive lighting. LED lights are very attractive because they are efficient, cost-effective and very powerful however there may be a new use for LED lighting on the horizon: high-speed data transmissions.
BBC News recently reported on new research being undertaken in a joint project between the universities of Cambridge, Edinburgh, Oxford, St. Andrews and Strathclyde. The project has enabled researchers to achieve data transmission speeds of 10 GBits per second using specially designed LED lights capable of utilising what is known as orthogonal frequency division multiplexing (OFDM).
Researchers explained their technique as being similar to what a showerhead does. Just as a showerhead splits water into dozens of individual streams, the modulators in the customised LED lights split the blue, green and red light spectrums into dozens of individualised streams that can carry binary data.
By controlling the modulation of each of the light streams, researchers have been able to transfer data to computers with a wireless system they are now calling ‘Li-Fi’. In theory, the technology should make it possible to increase wireless network capabilities exponentially. A commercially viable implementation of the technology will most certainly revolutionise data communications.
The idea behind Li-Fi goes back a few years to the University of Edinburgh's Prof Harald Haas, one of the current project's most influential leaders. Since his first demonstration in 2011, other researchers have been able to design and build LED bulbs capable of handling data communications at high rates of speed.
In Germany for example, researchers were able to achieve data transfer rates of up to 1 GBit per second, per light frequency, under optimal conditions. Chinese researchers have achieved speeds of 150 MBit per second with a single bulb, providing data communications for four computers.
Besides the obvious increase in speed, Li-Fi offers other advantages as well; amongst which is a huge improvement in local network security. Because light waves cannot penetrate solid objects, it would be entirely possible to have a secure Li-Fi connection inside a single room that could not be accessed externally. That capability could be extended throughout the entire office building with only a few modifications.
Another advantage is that light, when properly spaced and focused, does not suffer from the same degradation consistent with radio signals. Where traditional Wi-Fi signals may drop out, Li-Fi may remain strong. The potential here seems obvious in the world where radio-based Wi-Fi can be problematic.
Li-Fi technology promises to change how we think about wireless data communications. Combined with fibre optics and other superfast technologies now emerging, we could be on the verge of a completely new era of digital communications.
Is it any wonder that the current research is being undertaken in the UK? Not when you realise the UK leads the way in digital technology developments in Europe. This project is yet another example of what the UK technology sector has to offer and it's all good.