18-Mar-2017: 'Li-Fi' LED light bulbs to transmit wireless data at gigabit-level speeds

Researchers have devised a new method that relies on central 'light antennas' to beam rays of different wavelengths to wireless devices - meaning networks won't get jammed by several competing devices.

A light-based system 'Li-Fi,' could make wireless networks much more secure. It can transmit at the speed of 40 Gbit/s per ray. It would rely on direct rays of light from an optical fiber, and as it has no moving parts, it would be a maintenance free system that requires no power.

The direction of the ray of light can also be changed by adjusting the wavelength. The light-based network can track the precise location of each wireless device based on its radio signal. To add more devices, different wavelength can be assigned from the same antenna.

While current Wi-Fi systems rely on radio signals with a frequency of 2.5 or 5 gigahertz, the new network would use infrared light with wavelengths of 1500 nanometers or more. According to the researchers, this light can achieve much higher frequencies - up to 200 terahertz - for much greater capacity.

The system also uses visible light communication between 400 and 800 terahertz to transmit messages in binary code. Visible light cannot pass through walls, making Li-Fi a much more secure system, and less susceptible to interference.

While the system seems promising, it won't likely replace Wi-Fi entirely, at least not anytime soon. Instead, researchers are now looking to retrofit devices with Li-Fi to use the two wireless systems together to optimize speed and security.