LED lighting: civil time 2017 or high-speed Internet promotion

Do not have to find a WIFI signal, a point of LED lights will be able to achieve high-speed Internet access? This is not a fantasy. Recently, the school of information science and engineering, Fudan University, the good news came out, quickly aroused widespread concern. The research group led by Professor Chi Nan, the network signal access a 1W LED light bulb, under the light of the 4 computer to the Internet, the highest rate of up to 3.7G, the average net rate reached 150M, created the "lights on the Internet" speed world record. Next month, the 10 prototype will be unveiled in 2013 Shanghai industrial fair.

So, how far away from us? Reporters found that not too close, there are a lot of problems need to be resolved industrialization; said far too far, the relevant person in charge of Shanghai broadband center, should be able to promote in 2017.

Pregnant women do not have to worry about radiation

Light Internet, not the first Fudan University. As early as 2000, Japanese scientists began to study the new technology. 2011, the technology for the first time a physical research, a major breakthrough. German physicist Harald Haas and his team at the University of Edinburgh in the UK, to transmit digital information by flashing lights, this process is called visible light communication (VLC), they applied for a patent, aptly called LiFi".

In recent years, visible light communication has become the field of international communication research, the United States, Europe, Japan and other countries of communication researchers, are competing for research. According to reports, the focus of competition is the transmission rate. Earlier this year, the Department of communication engineering, Fudan University, Department of Communication Engineering Research Group has just published a visible light transmission rate of scientific research results in 1.5G, the speed of the international academic community will soon refresh. Just a few days ago, late Professor Nan task group in the laboratory to create a new record of the transmission speed: M offline maximum one-way transmission rate of 3.7G, the average rate of real-time system access to 150M.

According to reports, last year, the Shanghai Municipal Science and Technology Commission has been in the city's universities and research institutes in the layout of the international advanced wireless communication technology, broadband center, Fudan University, Shanghai Institute of Technical Physics and other units jointly undertake visible light communication key technology research and application "project, Chi Nan Ren project leader.

Professor Nan introduced, as well as radio waves, are a kind of electromagnetic wave, the basic principle of network signal transmission is consistent. In the study, the ordinary LED bulbs on the microchip, can control it millions of times per second flashing, lit 1, out of the representative of the 0. Because the frequency is too fast, the human eye can not be detected, but the photosensitive sensor can receive these changes. In this way, the binary data is quickly encoded into a light signal and effective transmission. Under the light of the computer, through a special set of receiving devices, read the lights in the Morse code".

"LiFi has no radiation, it belongs to a visible part of the natural spectrum, so the human lighting has been shining for thousands of years, unlike some of the microwave signal, has been very strong, but you can not see it. Chi Nan introduced, compared with the already popular WiFi, the future of visible light communication security and economic. WiFi electromagnetic radiation, wireless signal through the wall, the network information is not safe. The light communication is more secure, you can achieve a place where there is light, there is a network signal. Turn off the lights. Moreover, the VLC spectrum is 400T-800THz, wireless communications in the 2-5GHz or so, the spectrum is 10000 times larger than the radio spectrum, which means greater bandwidth and higher speed, VLC more high-speed potential.

So the Internet can be used for secret communications, because as long as blocking the light, blocking the signal. For pregnant women, with the lights on the Internet, you do not have to worry about network radiation. LiFi can also be applied to a variety of special places, such as underwater operations, because WiFi technology uses radio communications, but can not penetrate the water, visible light can be. There is a high degree of sensitivity to radio interference, such as aircraft, operation room, lighting is also very suitable for the internet.

Can broadcast high-definition TV all day

In the laboratory, the task force is not only the use of visible light transmission signal, and achieve a "four", that is, to light a small lamp, the 4 computers can simultaneously access the Internet, the network signal transmission. Because of the speed of transmission to create a world record, so the computer in the laboratory, with the lights on the Internet can be connected to the TV to watch the video. "Our prototype is relatively stable, the test can be played continuously high-definition TV a day no problem. Chi Nan introduction, VLC transmission rate and transmission distance are mutually constrained, the current Fudan laboratory to achieve the 150Mb/s rate, you can pass 3 meters, 10Mb/s rate can pass the 15 meters.

Data upload program, we summed up there are 3, one is a two-way visible light communication, which requires a notebook LED lights. Followed by the downlink visible light, uplink infrared. There is a half light mode, down visible light, uplink wireless way. Chi Nan introduction, at present, the task force made a total of 10 prototype. Among them, there is a downward visible light, the prototype of the uplink infrared mode, that is, the emission signal is visible with the LED bulb, and the infrared signal is sent by the computer.

Due to the light on the wall, such as blocking the Internet can not be achieved, so the project team is also currently studying dark led communications, is in the weak light environment of the internet. In addition, the delay is also carried out in the electromagnetic spectrum of other bands of communication research, such as Q band, W band communications, these bands into