A team of German engineers from the Fraunhofer Institute for Applied Solid State Physics have broken the record for wireless internet transmissions. But the infrastructure required to achieve it is unlikely to become widely available any time soon.
The institute, which specialises in semiconductor and optoelectronic research, claims that the technology could transfer a conventional DVD in just under 10 seconds. The experiment also involved researchers from the University of Stuttgart.
“Data rates of six gigabits per second were achieved by the group through efficient transmitters and receivers at a radio frequency of 71-76 GHz in the so-called E band, regulated for terrestrial and satellite broadcasting,” claimed the institute.
It continued: “To squeeze in that amount of data requires an impressive signal-to-noise ratio, to avoid having to waste bandwidth on error-correction. So the team built a system of ultra-efficient transmitters and receivers. The transmitters are based on semiconductor chips made of gallium-nitride, which provide a high-power signal that’s transmitted from a focused parabolic antenna.
“The team beamed the signals between a 45-story tower in central Cologne and the Space Observation Radar in Wachtberg, 23 miles away. At the receiver, the researchers used special low-noise amplifiers built using indium-gallium-arsenide transistors. Their sensitivity allows them to detect incredibly weak signals.”
While the equipment used was highly specialised (and expensive), and utilised bandwidth reserved for broadcasting, the institute claims that it could be used to provide internet connections to locations where a wired connection wouldn’t be economic. A single transmission beam could be used to supply as many as 250 internet connections running at 24Mbps, they claimed.
The experiment was carried out by Project ACCESS (Advanced E Band Satellite Link Studies), a research group headed by Professor Ingmar Kallfass from the Institute of Robust Power Semiconductor Systems (ILH) from the University of Stuttgart, and including the Institut für Hochfrequenztechnik und Elektronik (IHE) from KIT, Radiometer Physics GmbH, and the Fraunhofer Institute for Applied Solid State Physics IAF.