NTIA, Defense Release National Spectrum Strategy Study on Lower 37 GHz Band

WASHINGTON, Dec. 4, 2024 – Federal spectrum managers and the Defense Department announced Tuesday a plan for sharing the lower 37 GigaHertz (GHz) band.

It’s the first study published as part of the national spectrum strategy, a Biden administration plan to study federal bands for potential repurposing.

Lower 37 GHz spectrum has much higher capacity than the airwaves traditionally used for 5G networks, making it useful for fixed and mobile broadband, but the spectrum doesn’t propagate as well through obstacles or over long distances. The military uses the band at more than a dozen sites across the country.

The National Telecommunications and Information Administration, which manages federal spectrum, and the Defense Department endorsed a framework with two phases. First, propagation models would be used to check whether a proposed site might interfere with other users based on various parameters. If the answer is yes, the applicant would have to provide more detailed information to the National Telecommunications and Information Administration, which would coordinate with incumbents to work out how coexisting might work.

“The result of this phase could be the proposal of additional interference mitigation techniques, such as antenna directivity, polarization, or shielding to provide solutions in specific situations without requiring a one-size-fits-all approach,” the agencies wrote.

It’s in line with what the Federal Communications Commission, which manages commercial spectrum use and would have to implement the plan, put forward in September.

Also in line with the FCC proposal, the NTIA and Defense endorsed giving the military priority access, meaning commercial users would have to accept its interference, in the bottom 200 megahertz of the band. The remaining 400 megahertz would be available to industry and the government on a co-equal basis.

The 200 megahertz of priority DoD access would be “a 'proving ground' for technological solutions for unique military user needs,” the NTIA and Defense said in a joint statement.

Major mobile carriers, which own similar spectrum known generally as millimeter wave, and other companies generally supported the two-phase approach when the FCC published its public notice.

The NTIA and DoD proposed an additional measure: adopting a measure from the 2019 World Radio Communication conference that would strengthen interference protection for adjacent bands. The upper 37 GHz band, the agencies said, also has important military and scientific uses. Indeed, a group of researchers asked the FCC to include the measure in any adopted framework to protect weather forecasting data and other space-based research.

The FCC had also floated the idea, and industry commenters opposed it, saying the move would be unnecessary. 

The lower 3 GHz band and the 7-8 GHz band, both of which are better suited for 5G networks than millimeter wave spectrum like lower 37 GHz, are also being studied as part of the national spectrum strategy. Those reports are due in October 2026.