High data rate Li-Fi prototype

March 28, 2014 // By Paul Buckley
A prototype for wireless high data rate Li-Fi transmission is to be demonstrated by CEA-Leti at the upcoming Light + Building 2014 in Frankfurt, Germany. The device achieves throughputs of up to 10 Mb/s at a range of three meters.

The technology employs the high-frequency modulation capabilities of light-emitting diode (LED) engines used in commercial lighting.

The device achieves 10 Mb/s transmission rate at a range of three meters using light power of less than 1,000 lumens and with direct or even indirect lighting.

With this first proof of concept and its expertise in RF communications, Leti is forecasting data transmission rates in excess of 100Mb/s with traditional lighting based on LED lamps using this technology approach and without altering the high-performance lighting characteristics.

The optical system consists of an A19 lamp based on LEDs at the transmitter and an avalanche photodiode at the receiver. The digital communication component is implemented on a proprietary and reconfigurable platform that carries out a flexible multi-carrier modulation.

As part of its Ecodesign process, the European Union has established a schedule for LED lighting penetration (regulation No. 1194/2012) which will help drive Li-Fi technology developments. Halogen lamps will be phased out and replaced by LED lighting by Sept. 1, 2016, in 30 European countries.

Moreover, because LEDs can be modulated at high frequencies and their oscillations are invisible to humans, they permit information transmission at high data rates.

Other technical and market factors also are increasing interest in data transmission through lighting. These include crowding of the conventional RF spectrum, the mobile data-traffic explosion in cellular networks, and the need for wireless data transmission without electromagnetic field (EMF) interference.

The demonstration is part of a Leti project begun in 2013 to achieve a high data rate Li-Fi prototype by applying Leti’s expertise in digital communications, hardware prototyping and solid-state lighting.

Leti, which is demonstrating the Li-Fi capability to show a promising alternative to conventional RF wireless communications, is also focusing on component optimization to offer a bidirectional link.