Li-Fi inventor Harold Haas at TED Talks International
Original Post: The Low-Down on Li-Fi
VLC has become increasingly popular for smart tech and the Internet of Things as it does not rely on the radio spectrum that Wi-Fi relies on. Instead, Li-Fi relies on a light source, and the transfer to LED lighting across the world is making the transition to Li-Fi, and faster mobile internet, more feasible. Paris Metro has just confirmed a contract with Oledcomm to roll out 250,000 LED luminaires in 66 Metro stations with Li-Fi installation, allowing the Metro's two million daily commuters to access their mobile internet at a much faster speed (224 gigabits per second) than Wi-Fi could ever provide. In fact, the visible light spectrum is 10,000 times larger than the radio frequency spectrum that Wi-Fi uses, and Li-Fi will be more useful in electromagnetic sensitive areas like airplanes, nuclear power plants and hospitals.
How it Works
An LED bulb with a photo-detector sit at the center of Li-Fi transmission: The LED bulb is fitted with signal-processing technology embedded in its light beam, which transmits the information to the photo-detector, and a receiver dongle converts the information into an electrical signal, which is then streamed into your mobile device, allowing you to stream video up to 100 times faster than you could with Wi-Fi. It is also purported to be more private than Wi-Fi currently is, as the network remains limited to those within its beam of light.
The caveat is that in order to use Li-Fi, you will need to stand under a light source-- with the light on-- in order to transmit data. Leaving the illumination of that lamp, and you leave behind your internet connection. Li-Fi also cannot penetrate through walls. As of now, Li-Fi is suggested to be used in conjunction with Wi-Fi, which has a larger area of use, although at slower speeds with less reliability.
The ability to save money and consume less energy, while providing high speed internet, is a real advantage for the LED lighting industry and for everyone waiting for the Metro in Paris. Hopefully this technology will continue to be adapted worldwide, making streetlights in all corners of the earth semi-conductors for high speed internet usage.
The History of Li-Fi
Li-Fi was invented in 2012 by Harold Haas, a Professor and Chairman of Mobile Communications at the University of Edinburgh in Scotland, and who coined the term Li-Fi during his TED Talk in 2011. He is also the co-founder of pureLiFi. Haas discovered that flickering an LED could transfer data much more rapidly than a typical cell tower (1 Gigabit per second). This led to he and his researchers developing a system with VLC into toggling a light switch thousands of times per second-- faster than the human eye can detect-- to create a stream of "on" and "off" pulses that can be interpreted by the technology as binary code to transfer data.
Since then, many tech companies around the world have been competing in the research and development of this technology. Oledcomm, headed by Suat Topsu, is one of the most successful in their claims to producing the fastest data transfer through Li-Fi, and have landed the largest accounts, Paris Metro being no exception.
Apple is rumored to be developing their next iPhone to be VLC compatible.