One of the most hotly contested bits of real estate today is one you can't see. As we move into an increasingly wireless-connected world, staking out a piece of the crowded electromagnetic spectrum becomes more important. DARPA is hoping to help solve this issue with its latest Grand Challenge, which calls for the use of machine-learning technologies to enable devices to share bandwidth.

The Spectrum Collaboration Challenge (SC2) is aimed at alleviating an ongoing technological headache. Ever since the invention of radio, it's been recognized that there is only so much of the electromagnetic spectrum to go around, so government regulations were imposed to allocate bandwidth.

Early broadcast technology was fairly crude and radio and television services, for example, were given whole regions of the spectrum that today seem like allocating the entire Missouri river basin to run a toothpick factory. In recent decades, the rise of digital technology has pushed a reshuffle of these allocations that has also sparked a lot of bickering in military and civilian circles over who gets what and how much.

The SC2 is based on the idea that wireless devices would work better if they cooperated with one another rather than fought for bandwidth. Since not all devices are active at all times, the agency says, it should be possible through the use of artificial intelligence machine-learning algorithms to allow them to figure out how to share the spectrum with a minimum of conflict.

DARPA announced the competition in front of 8000 engineers on Wednesday at the International Wireless Communications Expo (IWCE) in Las Vegas. SC2 will run from 2017 through 2020 with teams competing to create radios that can collaborate most effectively with other radios. The competition will end with a live event and the prize is US$2 million.

To host the event and act as a venue for further research, DARPA is building the largest-of-its-kind wireless testbed called the "Colosseum" after the famous arena in Rome. This will allow researchers to carry out large scale tests in a controlled environment that can be configured to simulate real-world problems.

"DARPA Challenges have traditionally rewarded teams that dominate their competitors, but when it comes to making the most of the electromagnetic spectrum, the team that shares most intelligently is going to win," says SC2 program manager Paul Tilghman of DARPA's Microsystems Technology Office (MTO). "We want to radically accelerate the development of machine-learning technologies and strategies that will allow on-the-fly sharing of spectrum at machine timescales."

DARPA will release a Broad Agency Announcement for SC2 in the near future. In addition, there is a website for the latest information on the challenge.