Combining LED and IoT, LiFi may be applied to smart cities and information security

LiFi looks like a relative of WiFi at first glance, but in fact it is a kind of visible light communication (VLC), which uses the light emitted by fluorescent lamps or LED lamps as a signal source, and transmits information by communication between the light source and the receiver. At present, many countries value these advantages and begin to develop this technology.

Among them, the Ministry of Information and Communications of India (MeitY) is now working with the Indian Institute of Technology (ITT) and Philips India to study LiFi technology, hoping to complement the fiber optic network, using the technology in areas without fiber optic networks but with electricity, and using In the hospital or diving equipment. According to their research, at a range of 1 km, LiFi can reach speeds of 10GB per second.

Neena Pahuja, managing director of the Network Education Research Unit (ERNET) of the Ministry of Information and Communications, said that LiFi can be used in smart cities, and these communication technologies will become the main infrastructure in India. LED bulb connection.

ERNET has been experimenting with ITT and Philips in the lab before, and the technology is about to enter the outdoor testing phase, Pahuja pointed out that the new technology will then be tested outdoors at the Indian Institute of Science and Technology (IISc) in Bangalore, India.

LiFi was first launched in 2010 by Harold Haas, a professor at the University of Edinburgh. According to the research report at the time, LiFi can simultaneously complete two functions of high-speed Internet access and lighting. However, although it has the advantages of high-speed transmission and high security, as long as the light is blocked or blocked, the signal will be interrupted.

Pahuja said that LiFi cannot penetrate walls and requires unobstructed space to transmit signals, and it is widely used in the market for some distance. And we think mesh of LED lights is a solution. And India Jawaharlal. Researchers at the Nehru Centre for Advanced Scientific Research (JNCASR) also agree with this approach. Laboratory professor KS Narayan said that although the walls can reflect light, the signal will be weakened and we can use more light bulbs to maintain the signal source.

LiFi information security and new research fields

JNCASR is currently committed to improving the security of LiFi, hoping to improve network security in future smart cities. The researchers painted walls with fluorescent and phosphorescent paints, which absorb light and increase noise, limiting the range of LiFi usage.

But after absorbing light, phosphorescent paint can continue to emit light after the light source is turned off. This phenomenon also opens up a new field of research. Narayan pointed out that if the light emitted by phosphorescent paint can be used as a signal source, it means that even when the light is turned off, phosphorescence can be A signal that lasts for hours.

French company Oledcomm launched LiFi products at CES in 2014, which can transmit information at high speed with pulsating flashes that are invisible to the naked eye. The American company VLNComm is also developing the first Li-Fi LED lighting panel this year. It is equipped with white LEDs and provides a download speed of 108Mbps. It can also be used with the "LumiStick" with an upload speed of 253Mbps, and the network domain is 516 square feet.