If you listen to environmentalists and home building experts, the future of lighting lies in LEDs (Sorry to break it to you, CFL bulbs). But could LEDs also hold the key to the future of wireless home networking? Yeah, it sounds weird, but scientists at the Fraunhofer Institute for Telecommunications in Berlin got the bright idea to try and create a WLAN using nothing more than standard LED bulbs and "a few additional components." And you know what? It worked, and it worked well.
The scientists managed to create a wireless network capable of 800Mbps speed using the same red, blue, green and white LEDs that you can find in things like Christmas lights. Using white LEDs only resulted in 100Mbps speeds. They placed the LEDs on the roof and achieved 10 sq. meters of data coverage by rapidly blinking the lights on and off. Receivers can pick up the signal as long as they're in the coverage area. The network can even stream HD-quality videos with no lag or loss in quality.
"For VLC (visible light communication) the sources of light – in this case, white-light LEDs – provide lighting for the room at the same time they transfer information," Dr. Anagnostis Paraskevopoulos explained in the facility's press release. "With the aid of a special component, the modulator, we turn the LEDs off and on in very rapid succession and transfer the information as ones and zeros. The modulation of the light is imperceptible to the human eye. A simple photo diode on the laptop acts as a receiver. The diode catches the light, electronics decode the information and translate it into electrical impulses, meaning the language of the computer."
It sounds like magic, but it suffers from one big technical drawback: whenever something comes between the LEDs and the receiver, the signal loses considerable strength. The institute says the technology would come in handy in places that require fast data transfer rates, but don't want to install new cabling and can't receive radio signals – hospitals and airplanes, for example.