New Wireless Internet Based on Infrared Rays

Scientists have developed a new wireless Internet based on infrared rays that is 100 times faster than existing Wi-Fi networks.

The wireless network developed by researchers at Eindhoven University of Technology in The Netherlands not only has a huge capacity — more than 40 Gigabits per second (Gbit/s) — but does away with the need to share Wi-Fi as every device gets its own ray of light.

Current Wi-Fi uses radio signals with a frequency of 2.5 or five gigahertz. The new system uses infrared light with wavelengths of 1,500 nanometres and higher.

Researchers managed to achieve a speed of 42.8 Gbit/s over a distance of 2.5 metres.

Even with the best Wi-Fi systems currenly available, users would not get more than 300 Megabit/s in total, which is some hundred times less than the speed per ray of light achieved by the new system.

The system has so far used the light rays only to download; uploads are still done using radio signals since in most applications much less capacity is needed for uploading.

The wireless data comes from a few central ‘light antennas’, which can be mounted on the ceiling, that are able to precisely direct the rays of light supplied by an optical fibre.

The antennas contain a pair of gratings that radiate light rays of different wavelengths at different angles (‘passive diffraction gratings’).

Changing the light wavelengths also changes the direction of the ray of light. A safe infrared wavelength is used that does not reach the retina in the eye.