Saturday, 19 October 2013

Progress to Li-Fi wireless light communication with LED lights which could reach hundreds of gigabits per second and even terabits per second

Chinese scientists have had successful experiments using Li-Fi technology, where wireless signals are sent by lightbulbs, according to Xinhua News.

Four computers under a one-watt LED lightbulb may connect to the Internet under the principle that light can be used as a carrier instead of traditional radio frequencies, said Chi Nan, an IT professor at Shanghai's Fudan University. 

She explained a lightbulb with embedded microchips can produce data rates as fast as 150 Mbps, much higher than the average broadband connection in China.

Current wireless signal transmission equipment is expensive and low in efficiency, said Chi.

Cell phones need millions of base stations to strengthen the signal but most of the energy is consumed on their cooling systems. Only 5 percent of the energy is used for actually transmitting the wireless signal.

The Li-Fi Consortium offers the fastest wireless data transfer technology available. Our current solutions cover effective transmission   rates of up to 10 Gbit/s, allowing a 2 hour HDTV film to be transfered within less than 30 seconds. Smaller files are transfered instandly.

This high speed technology can be extended to several 100 Gbit/s in later versions.

The development of a series of key related pieces of technology, including light communication controls as well as microchip design and manufacturing, is still in an experimental period.




German researchers demonstated 3 Gbps LED Li-fi in the lab and 500 mbps at a trade show. They used three different colors.

Light bulbs currently flicker a few tens of thousands of times per second but the human eye cannot detect it. 




Li-fi usually only uses a percent or a few percent of light level reduction.

Li-fi could be used to transmit signal through water and could be used to transmit information through car headlights for vehicle-to-vehicle data transmission.

"In the future you will not only have 14 billion (LED) lightbulbs, you may also have 14 billion Li-Fi's deployed worldwide for a cleaner, greener, and even brighter future," Haas said at the TED talk introducing the technology.