LEDs Could Provide Next Generation Wireless Li-Fi Connectivity
LED lighting comes with many advantages. They help you save money, last ages, and provide great quality light.
They could be about to give you quite literally lightning quick internet too.
A group of scientists working at the University of Edinburgh have discovered a way of turning an ordinary LED bulb into a wireless access point. It was given the name ‘Li-Fi’, by Professor Harald Haas during a TED Talk in 2011.
It uses a concept known as visible light communication (VLC), as method of transmitting data using visible-frequency signals. This works by switching a light source on and off very quickly.
So quickly in fact, that it is imperceptible to the naked eye – so you wouldn’t even notice it. The claims say that it can transfer data 100 times faster than standard Wi-Fi – with speeds of up to 224 gigabits per second.
It‘s something that is only possible using LEDs too. Fluorescent and incandescent lighting cannot flicker quickly enough to create the signals necessary for wireless internet.
A photo diode would be required on your laptop or computer, in order for it to read the light signal.
Have a look at the aforementioned TED Talk below for more information.
Naturally, comparisons will be made with the current industry Wi-Fi, which uses radio frequencies to transmit data.
There are in total 1.4 million cellular radio masts worldwide, with more than 5 billion cellular mobile phones around the world too. In total, these devices transfer more than 600 terabytes of data every month. Let’s also remember that there are 14 billion light bulbs deployed all around the world.
Radio waves represent a very small fraction of the electromagnetic spectrum. As the demand for wireless connectivity increases, the supply of available bandwidth diminishes.
Li-Fi doesn’t suffer from this problem, as the visible light spectrum is 10,000 times larger than the radio frequency spectrum.
If we multiply the 1.4 million masts by the difference in spectrum size – 10,000 – we end up with 14 billion, which is the number of lights in the world. This tells us that the infrastructure is there for Li-Fi.
Security is also key. Radio waves can pass through walls and doors, which means there is nothing other than a password stopping your neighbours from piggybacking on your wireless signal.
This isn’t a concern with Li-Fi though, as light cannot penetrate walls. The user must be in the same room as the LED lighting for data transfer to take place.
Another advantage with Li-Fi is that it is possible to use it in areas where Wi-Fi may cause problems or is just impractical, such as hospitals and aeroplanes.
The potential for internet way beyond what we know today could be possible using Li-Fi – imagine downloading a high-definition film in less than a minute.
The main aspects that are holding Li-Fi back are that it uses light – let’s go into this in a bit more detail.
We’ve already mentioned how security is less of a concern as light cannot pass through walls. This however is a double-edged sword, as it will also mean you’ll need every room in your home decked out with LEDs.
To add to this, your lights would need to be on even during the day when you don’t need them – otherwise you’ll have no internet connection.
Places that don’t have many lights would take a hit too, especially when it comes to public Wi-Fi networks.
That hasn’t stopped people pushing the tech. Professor Haas has set up a company called ‘pureLiFi’, with the aim “to be the world leader in Visible Light Communications technology”.
They already have 2 products on the market too – the Li-Flame Ceiling Unit that connects to an LED light fixture, and the Li-Flame Desktop Unit which connects via USB for a more portable option.
Even Apple has thought about the future of Li-Fi with regards to the iPhone. Twitter user Chase Fromm spotted the term “LiFiCapability” in iOS 9.1’s library cache file.
In the future, connecting to the internet might just be as easy as flicking on a light switch. There may be kinks in the technology now, but there’s no reason why these couldn’t be ironed out – much like the way LEDs themselves have progressed since coming onto the market.