Cheaper is better, as this technology promises. And it could replace cable expansion of networks across waterways, the last mile to the home, and other areas where a line of sight laser system, such as this, is more economical.
Researchers at the Karlsruhe Institute of Technology (KIT) in Baden-Württemberg, Germany, have addressed the issue of expanding cable-based telecommunication networks, which require large investments in both conurbations and rural areas, by using broadband data transmission via radio relay links to make the economies more feasible. In the current issue of the Nature Photonics Magazine, researchers present a method for wireless data transmission at a world-record rate of 100 gigabits per second.
In their world record experiment, 100 gigabits of data per second were transmitted at a frequency of 237.5 GHz over a distance of 20 m in the laboratory. In previous field experiments under the “Millilink” project funded by the BMBF, rates of 40 gigabits per second and transmission distances of more than 1 km were reached. For their latest world record, the scientists applied a photonic method to generate the radio signals at the transmitter. After radio transmission, fully integrated electronic circuits were used in the receiver.
“Our project focused on integration of a broadband radio relay link into fiber-optical systems,” Professor Ingmar Kallfass says.
He coordinated the “Millilink” project under a shared professorship funded by the Fraunhofer Institute for Applied Solid State Physics (IAF) and the Karlsruhe Institute of Technology (KIT). Since early 2013, he has been conducting research at Stuttgart University.
“For rural areas in particular, this technology represents an inexpensive and flexible alternative to optical fiber networks, whose extension can often not be justified from an economic point of view.” Kallfass also sees applications for private homes: “At a data rate of 100 gigabits per second, it would be possible to transmit the contents of a blue-ray disk or of five DVDs between two devices by radio within two seconds only.”
Last May the team had succeeded in transmitting a data rate of 40 gigabits per second over a longer distance in the laboratory using a purely electronic system. In addition, data were transmitted successfully over a distance of one kilometer from one high-riser to another in the Karlsruhe City center.
These projects are part of the German government funded Millilink initiative, to the tune of nearly $3 million. It's worth noting that the exiting record is based on one data stream. Interweaving of multiple data streams and other techniques could increase total available bandwidth by greater multiples without degrading the system's integrity.