Short for 'light fidelity', Li-Fi technology uses light to transmit data, compared to Wi-Fi which uses radio waves. Li-Fi is an emerging area of connectivity and a key market could be aircraft cabins.
Birger Timm, aeroLiFi, gave FINN a demonstration of Li-Fi in action [see video] – in this case to power an in-flight entertainment (IFE) system using a visible light link.
“[Li-Fi] also works with infrared lighting,” Timm said.
Timm explained that: “We are using the existing light positions [of lights in the aircraft cabin] to create a stable and secure, high-speed wireless link via light.”
Li-Fi effectively increases the data rate – or ‘data density’ – per passenger.
Timm said: “Many people can share one Wi-Fi network and all the passengers in an aeroplane [typically] share this one network so the data rate per passenger effectively goes down. When using Li-Fi technology, the effective data rate per passenger rises because [fewer] people share one access point. That's because every light can be an access point and by physical laws, hundreds of people can't gather under one light."
One of the features of Li-Fi is that it can’t pass through walls – unlike Wi-Fi.
This can be a benefit because it can increase security in certain applications. However, it clearly has limitations too.
aeroLifi uses a software solution which caches and buffers the data streaming to the IFE screens so if the light path is blocked for 10 or 20 seconds, viewing isn’t interrupted.