Wi-Fi network based on infrared rays

  

Capacity is said to be of more than 40Gbit/s per ray, and each device functions with its own ray of light. According to the team, the wireless data comes from a few central light antennas, for instance mounted on the ceiling, which can precisely direct the rays of light supplied by an optical fibre.

Since there are no moving parts, it is maintenance-free and needs no power. The antennas contain a pair of gratings that radiate light rays of different wavelengths at different angles. Changing the light wavelengths also changes the direction of the ray of light.

Once a smartphone or tablet moves out of the light antenna's line of sight, then another light antenna takes over. The network tracks the precise location of every wireless device using its radio signal transmitted in the return direction. Devices are assigned different wavelengths by the same light antenna and so do not have to share capacity.

Moreover, there is no longer any interference from a neighbouring Wi-Fi network. Current Wi-Fi uses radio signals with a frequency of 2.5 or 5GHz. The system uses infrared light with wavelengths of 1500nm and higher, which makes the data capacity of the light rays much larger.

The team managed a speed of 42.8Gbit/s over a distance of 2.5m. The Eindhoven system has so far used the light rays only to download.

The researchers believe the first devices to be connected to this new kind of wireless network will be high data consumers like video monitors, laptops or tablets.