Without WiFi, LED lights will be able to access point

2013/12/25

Without WiFi signal , an LED lamp can point the Internet . Yesterday, the Department of Computer Science and Technology, spread the good news , a signal transmission network use of the house visible international forefront of communications technology in the laboratory successfully . Researchers will access a network signal lamp 1W LED lamp beads, four computers to the Internet under the lights , the highest rate of up to 3.25G, the average Internet speeds of up to 150M, called the world 's fastest " light Internet ." Next month, 10 prototype will be unveiled in 2013 Shanghai International Industry Fair .

Visible light communication is called Lifi

Has been painted a shiny light bulb on a person's head, is used to symbolize an inventor 's idea came , but the German physicist Harald Haas from the bulb itself "light up" the Chin wonderful thought : rely a little light, the invisible network signal becomes " visible" network signal . Haas and his team at the University of Edinburgh 's latest invention, a patented technology that uses flashing lights to transmit digital information , this process is known as visible light communication (VLC), people often put it affectionately known as "Lifi", to show it to the currently represented WiFi wireless network transmission technology may bring a revolutionary change .

This is hard to imagine the network technology in the end far away from us ? The answer is: very close, it is she keeps us coming from Fudan University laboratory. Professor, Department of Computer Science and Technology, told reporters Xue Xiangyang , there are many limitations of current radio signal transmission equipment, they rare and expensive , but the efficiency is not high , such as mobile phones, millions worldwide to help them enhance the signal station , but most energy is consumed by the cooling efficiency of only 5%. In contrast, the light bulb was inexhaustible used worldwide , especially in large-scale domestic LED light source is to replace the traditional incandescent lamp. Just add a microchip in any humble LED bulb , you can let the bulb into a wireless network transmitters . ( Continued on Page A2 ) (on the first edition )

Visible communications security and economical

Beginning last year , the Shanghai Science and Technology Commission has universities and research institutes in the city layout of the international forefront of wireless communication technology, visible light communication technology research and application of the key commitments made important progress in Fudan University : researchers not only use in a laboratory environment visible light transmission network signals, and can achieve "a drag four ", that lit a small lamp , four computers to simultaneously access, network signal to each other . Professor Chi Nan research staff noted light and radio waves, electromagnetic waves belong to a basic principle of signal propagation network is consistent . Study, to ordinary LED bulbs mounted on a microchip , you can control it millions of times per second, flashing , indicating a bright , off represents 0 . Since the frequency is too fast , the human eye simply imperceptible , light sensors but they can receive these changes . In this way, the binary data is encoded into light signals fast and efficient transfer. Computer under the lights through a special receiver , read the lights in the " Morse code ."



"There is light where there is a network signal . Turned off the lights , the network no ." Chi Nan told reporters , compared with existing WiFi, visible future communications security and economical. WiFi rely on invisible radio wave transmission , power equipment is growing, is bound to enhance local electromagnetic radiation ; radio signals through walls , network information safe. These security risks in the visible communication " wiped out ." Moreover, a large spectrum of radio spectrum than 10,000 times , which means more bandwidth and higher speeds, network setup and virtually no new infrastructure .

Lifi technology has its limitations

Of course , still in the laboratory as a new network technology and products , its future potential should not be overestimated . "Because, from the lighting to the communication control chip design and manufacture of a range of key technology products , are the researchers ' hands-on ', so to really like WiFi into millions of households , through a series of industrial development, there is still a long way to go . " Chi Nan believes , Lifi technology itself also has its limitations , for example, if the light is blocked , the network signal will be cut off , and so on . Therefore, it is not WiFi competitor , but a complement to each other , to help release the spectrum space . Its future , the ability to produce killer -type applications, but also on the people endless imagination : between cars rely LED lights to "dialogue" , the use of aircraft passenger cabin overhead LED reading lights to the Internet ......