Project uses light to transmit data, crushes WiFi speeds
- — 22 January, 2010 12:16
A Siemens research project has recently broken the record for wirelessly transmitting data, by making use of white LEDs (light-emitting diodes) instead of radio waves. Siemens researchers here able to transmit data at 500Mbps, beating the previous record of 200Mbps, and completely obliterating current WiFi standards (though upcoming WiFi standards could push it into Gigabit territory).
Siemens researchers used Ostar LEDs, one of the brightest LEDs on the market. The lights are modulated at a frequency that allows for high-speed data transfers. On the other end is a photodetector that receives the light signals and converts them into electrical pulses.
Siemens refers to this method of transmitting data as VLC (Visible Light Communication), and the company claims that it could be put to use in numerous ways. It could be used to help boost the performance of wireless networks. For example, if you live in an apartment building where WiFi networks interfere with each other, VLC could be an alternative since visible light isn't currently used to carry data, so there would be significantly less interference.
Another advantage is that VLC data transfer is more secure than radio signals, since the receiving end must have a photodetector and a simple curtain is enough to stop potential eavesdroppers.
Other applications suggested are in transportation, where LED stoplights can transmit information to trains and cars, for example. Siemens mentions that they combined five LEDs to transfer data over "longer distances" at rates up to 100Mbit/s, but didn't mention exactly how long these distances were.
Also, there was no mention as to how other light sources might affect the data transfer, or how much distance negatively affected the data speed.