Shanghai Fudan University develops new Li-Fi technology

Want China Times, Staff Reporter 2013-10-18

A new light bulb design on display at the Hong Kong International Lighting
Fair, Apr. 6. (Photo/Xinhua)

Shanghai's Fudan University has made a breakthrough with the development of "Li-Fi" technology, in which a one watt LED light bulb can help connect four computers to the internet simultaneously, reports the local Xinmin Evening News.

Compared with an average internet connection speed of 150 megabytes per second (Mbps), the new technology — which uses light as a carrier instead of traditional radio frequencies used for Wi-Fi — can also generate speeds as fast as 3.25 gigabytes per second (Gbps), the university said.

The current wireless broadband connections are expensive and less efficient, said Xue Xiangyang, a professor at the university's Department of Computer Science. He cited the example of wireless services in mobile phones, where although there are many base stations set up to help increase the signals, efficiency rates are as low as 5%. On the other hand, LED lighting, which could be used to replace traditional devices, can provide a safer and cheaper solution by adding a microchip on the bulb, Xu said.

The Shanghai Committee of Science and Technology asked Fudan University to work on key applications to help develop the information industry last year, and the university will now showcase ten computer samples using the new technology at the Shanghai Industry Expo next month.

Chi Nan, a member of the research team, said that Wi-Fi, which depends on an invisible wave, has the hidden danger of electromagnetic radiation, while with Li-Fi technology, the light spectrum is 10,000 times more than the radio spectrum and it does not require any new infrastructure construction. He added, however, that there is still a long way to go before Li-Fi can be used by thousands of households as it would take time to manufacture a series of products, such as the connection control and chip at a mass production level.

Chi said that Li-Fi should not be treated as a rival to Wi-Fi connection but rather as a complementary technology, as the Li-Fi connection may be disrupted when the light is blocked.