The Defense Department is, perhaps, the biggest user of the spectrum within the United States. But for the U.S. to remain economically competitive, the DOD must share the spectrum. The DOD's chief information officer said it's possible to do that without compromising national security.
"As the DOD CIO, we absolutely get it at the Department of Defense that we need to balance our economic advantage by maximizing spectrum, as well as being able to preserve our national security responsibilities," said John Sherman, during a keynote address recently at the National Telecommunications and Information Administration's Spectrum Policy Symposium. "We have to be able to balance that."
China, named by the Defense Department as a pacing challenge, is moving along technologically, economically and militarily "at a very fast clip," Sherman said.
"I would say they're challenging us in many spaces — not just with defense and military, but in economic, technology, spectrum and otherwise," he said. "We all better be able to rise to the challenge of what they're presenting; finding the spectrum way ahead is critical to our nation."
Already, Sherman said, the DOD has had success in sharing spectrum with industry and doing it in a way that balances the Nation's defense and the needs of industry.
"Most recently, there was 'America's Mid-Band Initiative Team,' or AMBIT, making available spectrum to industry between the 3.45 to 3.55 [GHz] part of the spectrum, which raised in an auction last fall, $21 billion," he said. "That took a lot of work and a sprint by our collective team at DOD and working with the interagency to make that happen."
In August 2022, AMBIT identified a segment of spectrum from 3450-3550 MHz as available for sharing. Coupled with already available spectrum from 3550-3980 MHz, the effort created a contiguous 530 MHz band for use by the U.S. technology sector. The DOD was also part of establishing the sharing framework in the Citizens Band Radio Service, or CBRS, in the 3550-3650 MHz band.
Today, Sherman said, the DOD is working with partners, including NTIA, on finding ways to share the 3100-3450 MHz portion of the spectrum. The effort is called Emerging Mid-Band Radar Spectrum Sharing, or EMBRSS. The effort, he said, is built on the successes and lessons learned from other spectrum-sharing activities.
As part of EMBRSS, Sherman said, it's critical that DOD share, rather than give up entirely, access to the 3100-3450 MHz portion of the spectrum, considering the use of that spectrum by critical U.S. military radar systems.
"We have many radars ... land, air and sea-based, that are critical for our service members to train on before they deploy into harm's way overseas, and also to protect our homeland, day in and day out, both against threats such as Russian 'Bear' bombers flying off our coastline, to emerging threats from our pacing challenge that can reach out and touch our homeland in a conflict situation, as well as border security and other very important missions," Sherman said. "As I said during my confirmation hearing last fall, sharing of the spectrum space must be our watchword."
Vacating the 3100-3450 MHz band would take decades and would cost the DOD billions of dollars, Sherman said.
"But sharing offers us a way ahead out of this and we've proven we can do this with the other initiatives I've talked about," he said. "We can make sharing work in collaboration with you all in industry and with our interagency partners."
Sherman said the DOD has already held ten meetings as part of the Partnering on Advanced and Holistic Spectrum Solution, or PATHSS, task group established last year with the National Spectrum Consortium to bring together DOD, interagency partners, industry and academia to work through how the department can do spectrum sharing in the 3100-3450 MHz spectrum band.
"This is our effort to reach out [and] hear other voices — not just look at it through a defense prism, but try to balance all the different equities there," Sherman said.
A subset of the PATHSS task group, the PATHSS-C, he said, where the "C" is for "classified," is working at a classified level to get into the details of how DOD can share the spectrum used by military radars and still defend the nation.
"We're going to figure this out together," Sherman told industry attendees at the symposium. "I need your help as the DOD CIO to continue to get through this. And I don't say this with hyperbole about what it would take for us to move these radars. I want us to be successful economically, but I also want to work with you to ensure we can keep this nation safe, and our women and men safe downrange wherever they have to deploy now or in the future. And that is a sacred obligation I have as DOD CIO."