The light from the lamps in your house could carry a wireless signal that could power internet connectivity at home, say a group of German researchers who say they have found a way to encode the signals into visible frequency.

Though it would provide much lower speeds than Wi-Fi signals, it can offer less interference and is likely to offer great protection from hackers, say the researchers.

Currently, most homes use radio-frequency based Wi-Fi signals for broadband service. But Wi-Fi has limited bandwidth, says the researchers, and it is difficult to get more radio spectrum for it. Visible frequency would be a good alternative, they say.

Flickering the lights can generate the signal in a room. The change won't be visible to the human eye because the rate of modulation is millions of times faster than what we can see, say the researchers. And since, visible light can't penetrate walls there will be no interference.

Since incandescent and fluorescent bulbs can't flicker fast enough, LEDs would be the right choice, say the researchers.

Commercial LEDs have a bandwidth of only a few MHz. But Jelena Vučić, a researcher at the Fraunhofer Institute for Telecommunications, and her colleagues who have been working on the project have found a way to increase the bandwidth by filtering out all wavelengths but blue.

Using the visible wireless system they built, the team downloaded data at up to 230 megabits per second. The researchers will present their findings at a conference in San Diego later this month.

[via Inhabitat]

Photo: (slworking/Flickr)