DoD officials gear up for spectrum sharing 'moonshot'

Top US military officials reiterated the Pentagon's interest in spectrum sharing during a media event this week, describing the technology as a "moonshot" that would help the US maintain an advantage against its rivals both economically and militarily.

"This is a monumental event," DoD CIO John Sherman said Monday at a Washington, DC, event.

"I love that term," he said of the word "moonshot," explaining that it reflects the difficulty of the spectrum-sharing objective as well as the ingenuity it will take to reach it.

"I'm motivated by this," he said. "What gets me out of bed in the morning is doing hard things."

He continued: "It's on us – you and me – to figure out how we make this work."

The Biden administration earlier this year detailed its implementation plan for the national spectrum strategy it unveiled in November. The implementation plan will study how to allow commercial users in the lower 3GHz band that's currently used by the US military. However, the government's study of the job won't be done until 2026.

"I look forward to seeing what comes out of this," Sherman said of the study. "We're ready to move out."

Other DoD officials echoed Sherman's comments. 

"We're facing technical challenges that we can't do without you," said David Isaacson, another DoD official, in discussing the need for government, academia and industry to team up on the problem. "Working together is success."

And Steven Trueblood, the DoD official leading the Pentagon's work on dynamic spectrum sharing (DSS), said that such sharing technology represents "a massive engineering challenge," and that it's "challenging but doable."

"The time is now to scale our inspiration and our efforts," he said.

More of the same

The lower 3GHz band, which sits between 3.1GHz and 3.45GHz, pits the US military and the US wireless industry directly against each other. That's because the military currently operates radar and other functions in the lower 3GHz band, but the wireless industry wants to get access to the band for 5G.

According to wireless industry lobbying association CTIA, policymakers need to release the band for 5G so that the US can stay competitive on the international stage. But military officials generally argued that the band is necessary for a variety of military operations, including technologies designed to intercept missiles fired into US territory. As a result, DoD officials have voiced support for spectrum sharing but not for releasing the spectrum completely. The wireless industry generally wants exclusive access to the spectrum.

The DoD's position on sharing the lower 3GHz band is nothing new. When it released its 28-page "Electromagnetic Spectrum Superiority Strategy" in 2020, the document said the Pentagon "seeks to maintain military overmatch against its adversaries while sharing the spectrum with commercial partners."

More recently though, a top DoD official suggested the agency would consider moving some of its airborne radar operations out of the lower 3GHz band in order to free it up for 5G operations.

Wireless industry officials voiced support for the DoD's spectrum sharing efforts during the media event Monday. CTIA CEO Meredith Attwell Baker said "the world is becoming a more challenging place" and that the Pentagon and the wireless industry need to work together as a result. "This won't be easy," she said.

Regardless, the issue remains contentious.

For example, the DoD recently released a redacted version of its Emerging Mid-Band Radar Spectrum Sharing (EMBRSS) feasibility assessment. Almost two years in the making, the report outlines the challenges of spectrum sharing in the lower 3GHz band. After the release of the report, CTIA officials described the report as "incomplete" because it didn't look at other spectrum management techniques like retuning, relocating and repacking.

Nonetheless, DoD officials on Monday generally argued that the Pentagon and the wireless industry will need to work together over the next year or so to make spectrum sharing a reality. They argued that the sharing techniques pioneered in the 3.5GHz CBRS spectrum band will need to be expanded and improved, and that sharing will need to be mostly automated, although with human oversight.