WHAT IS LiFi?
Light Fidelity or LiFi is a Visible Light Communications (VLC) system running wireless communications travelling at very high speeds. LiFi uses common household LED light bulbs to enable data transfer, boasting speeds of up to 224 gigabits per second.LiFi and Wi-Fi are quite similar as both transmit data electromagnetically. However, Wi-Fi uses radio waves while LiFi runs on visible light. As we now know, Li-Fi is a Visible Light Communications (VLC) system. This means that it accommodates a photo-detector to receive light signals and a signal processing element to convert the data into ‘stream-able’ content.
HOW DOES IT WORK?
An LED light bulb is a semi-conductor light source meaning that the constant current of electricity supplied to an LED light bulb can be dipped and dimmed, up and down at extremely high speeds, without being visible to the human eye.
For example, data is fed into an LED light bulb (with signal processing technology), it then sends data (embedded in its beam) at rapid speeds to the photo-detector (photodiode).
The tiny changes in the rapid dimming of LED bulbs are then converted by the ‘receiver’ into an electrical signal.The signal is then converted back into a binary data stream that we would recognise as web, video and audio applications that run on internet enabled devices
LiFi Vs WiFi
Li-Fi signals cannot pass through walls, so in order to enjoy full connectivity, capable LED bulbs will need to be placed throughout the home. Not to mention, Li-Fi requires the light bulb is on at all times to provide connectivity, meaning that the lights will need to be on during the day.
Due to its shorter range, Li-Fi is more secure than Wi-Fi and it’s reported that embedded light beams reflected off a surface could still achieve 70 megabits per second. Li-Fi could make a huge impact on the internet of things, with data transferred at much higher levels with even more devices able to connect to one another. Where there is a lack of light bulbs, there is a lack of Li-Fi internet so Li-Fi does take a hit when it comes to public Wi-Fi networks.
LiFi is also more suitable in electromagnetic-sensitive areas like hospitals, airplane cabins, and nuclear power plants (where electromagnetic disturbance can be disastrous).
CURRENT USE OF LiFi
PureLiFi a French lighting company already has two products on the market: Li-Flame Ceiling Unit to connect to an LED light fixture and Li-Flame Desktop Unit which connects to a device via USB, both aiming to provide light and connectivity in one device.
Last year, it was reported that Li-Fi was being tested in Dubai, by a UAE-based telecommunications provider, du and Zero1. Du claimed to have successfully provided internet, audio and video streaming over a Li-Fi connection.
Apple may build future iPhones with Li-Fi capabilities. A Twitter user found that within its iOS 9.1 code there were references to Li-Fi written as ‘LiFiCapability’ hinting that Apple may integrate Li-fi with iPhones in the future.Airbus says it’s developing Li-Fi applications for aeroplane cabins and outside use.