Researchers at the Fraunhofer Institute for Applied Solid State Physics and the Karlsruhe Institute for Technology have transmitted a 40 Gbps data stream at 240 GHz across a distance of one kilometer, achieving what is said to be a world record in this portion of the spectrum.
The Fraunhofer press release, New World Record in Wireless Data Transmission
says “Their most recent demonstration sets a new world record and ties in seamlessly with the capacity of optical fiber transmission. In the future, such radio links will be able to close gaps in providing broadband internet by supplementing the network in rural areas and places which are difficult to access.”
Project Millilink used fully integrated electronic transceivers set up on two skyscrapers.
“We have managed to develop a radio link based on active electronic circuits, which enables similarly high data rates as in fiber-optic systems, therefore allowing seamless integration of the radio link,” said Professor Ingmar Kalifass, coordinator of the project at Fraunhofer IAF. “The device uses 80 GHz of spectrum between 200 and 280 GHz. The atmosphere has less attenuation at this frequency.
Jochen Antes of KIT noted that: “This makes our radio link easier to install compared to free-space optical systems for data transmission. It also shows better robustness in poor weather conditions such as fog or rain.” There is room for improvement. Antes added, “Improving the spectral efficiency by using more complex modulation formats or a combination of several channels, i.e. multiplexing, will help to achieve even higher data rates.”
This technology could be ideal for providing the last kilometer connection for “fiber to the home” services, especially in rural areas where it could be a cost-effective and flexible alternative to fiber.