The team led by imec’s Ingrid Moerman designed a system that excels in quality of service and the ability to cope with unexpected scenarios. Moerman leads the wireless research at IDLab, an imec research group at Ghent University. According to her, systems like these are the future for highly reliable wireless connections, for example in Industry 4.0 environments. The team is now upgrading its radio for SC2’s final and most challenging stage.
Coffee shops run rusty communication
Picture a familiar situation, a coffee shop where you try to browse the Internet and get some work done, only to get frustrated by the slow Wi-Fi.
Upgrading to the newest type of Wi-Fi router that touts extreme throughputs doesn’t bring much relief. It is the way the radio spectrum is organized that is to blame. Today, about half of the world’s Internet traffic is relayed over two small frequency bands. With the explosion of data traffic, these get forever more choked.
In fact, nothing much has changed since Marconi sent the first wireless signal across the oceans back in 1901. A wireless link between two appliances still relies on the fact that the two parties have agreed beforehand over which frequency they will communicate.
Following, the frequency spectrum has been divided into rigidly and exclusively licensed bands, each reserved for one type of communication. Only a few narrow unlicensed bands can be used freely, and these have been occupied by Wi-Fi for wireless internet, Bluetooth communication, or IoT traffic. In these unlicensed bands, traffic has exploded. In most licensed bands, in contrast, the spectrum is either underutilized or hardly used. Think of bands that are reserved for emergency communication or for sporadic bursts from satellites.
To develop new spectrum sharing strategies and overcome this steadily worsening situation, the USA Defense Advanced Research Projects Agency (DARPA) set up SC2, a competition consisting of three stages, with progressively harder goals.
Bringing on innovation through gaming
Ingrid Moerman: “The idea is that the teams enter the competition with an innovative system for wireless communication that is able to share spectrum with competing radios by scanning the spectrum for free spectrum holes. The main goal is to support more traffic with a quality of service that is much better than would be possible with fixed spectrum allocation. This of course without interfering with the radios that have the licensed rights to operate in those bands.”
“In the competition, the organizers play out a number of scenarios where the various radios have to collaborate to run applications to the best of their abilities. One of the scenarios, for example, is set at a shopping mall with a coffee shop, a restaurant, and a number of other companies. Each of those has separate communication nodes that are accessed by varying numbers of customers and data loads throughout the day. For each scenario, a great number of games is played. And each game involves a number of access points and a selection of team radios that should collaborate to achieve the best outcome.”