Twin shared-spectrum efforts close in on milestones

Two trailblazing efforts backed by DARPA and the FCC to share radio spectrum among federal and commercial users will hit significant milestones in the coming weeks.

wireless spectrum (Creations/

The Defense Department's research arm is in the final stretch of a key competition that agency officials think could be crucial to their wireless spectrum holdings, as another federally backed spectrum-sharing effort is commercialized.

On Sept. 10, the Defense Advanced Research Project Agency announced10 teams that will participate in the final leg of its software-defined radio competition next month.

The competition set for Oct. 23 at the Mobile World Congress in Los Angeles, where participants will show how their software-defined radio solutions can allow federal and commercial users to share the same scarce radio bandwidth.

The event marks the end of a three-year-long competition by DARPA to foster development of collaborative machine learning to overcome the increasingly cramped radio frequency spectrum. Although the first place winner will get a $2 million prize, federal agencies will be watching for efficient, effective technologies that could help them with their spectrum management struggles.

The final competition will shortly follow a spectrum-sharing project landmark.

In the coming days, another milestone spectrum-sharing program is set for commercialization. The initial commercial deployments of the Citizens Broadband Radio Service will begin in mid-September after collaboration between a three-year-old commercial alliance and federal spectrum holders. An exact date for the first offerings hasn't been set, but the CBRS Alliance is holding an event Sept. 18 for its members and federal spectrum officials to commemorate the first CBRS commercial service offerings.

Launched in 2015 under rules adopted by the Federal Communications Commission, CBRS is a program developed between federal users and commercial companies that shares spectrum in the 3.5 GHz band between incumbent Navy radar systems and commercial users.

Spectrum's future, Commerce Department's Deputy Secretary Karen Dunn Kelley said in a Sept. 10 speech at the National Telecommunications and Information Administration's spectrum symposium, depends on developing an overarching framework for spectrum. That framework, she said, should include dynamic spectrum sharing among commercial and federal spectrum users.

Sharing spectrum, she said, "requires us to think beyond the traditional model of 'one allocation, for one license, for one use.'"

The Pentagon is developing dynamic spectrum access frameworks it plans to share with NTIA,  Col. Frederick Williams, director spectrum policy and programs in the Defense Department CIO's office, said at the same event.

Williams said DARPA's spectrum challenges for software-defined radio networks "pushes the envelope" on use of spectrum in congested space.

DARPA's group of 10 finalists headed to Los Angeles next month, include academic, independent contractor and commercial industry teams.

According to the agency, the teams use a variety of AI techniques and technology, including "rule-based" approaches and pattern recognition powered by machine learning to prevent radio traffic in the shared bandwidth from interfering with each other. Some teams leverage both, it said.