FCC weighs 482 MHz D2D expansion despite carrier objections

Daniel Okafor

The US FCC is seeking feedback on a 482 MHz expansion for direct-to-device services, while AT&T, T-Mobile and Verizon seek to exclude the contested 2.5 GHz and 3.45 GHz 5G bands.

The current proposal would increase the number of bands authorized for supplemental coverage from space, or SCS, from five to 13. The FCC describes 482 MHz as the potential grand total. It has not allocated the spectrum or adopted rules.

The aim is more capacity for D2D services used to fill coverage gaps in terrestrial wireless networks. The FCC will assess coexistence through public comments and a final NTIA study.

Which 5G bands are under contention?

The contested, heavily used bands are 2.5 GHz and 3.45 GHz. AT&T, T-Mobile and Verizon say operating D2D services there would cripple 5G network performance. All three want the FCC to remove both bands from the proposal.

Their objection centers on a duplex mismatch. Time-division duplex, or TDD, technology operates in the 5G bands, while D2D would use paired frequency-division duplex, or FDD. The carriers say that combination would degrade their respective 5G networks.

T-Mobile says sharing 2.5 GHz would produce dropped calls and cripple its uplink coverage. The released material gives no dropped-call rate or throughput loss. The warning therefore remains a carrier claim, not a measured operating result.

It remains unclear whether 2.5 GHz and 3.45 GHz will enter a follow-on rulemaking. The warning as presented does not quantify the effect on 5G users.

Where does the NTIA study fit?

FCC Chairman Brendan Carr said: "There are important technical questions to answer about whether satellite and terrestrial uses can successfully coexist in the bands we consider today." He said he would monitor a final study from the National Telecommunications and Information Administration on the issue.

That study is not yet complete. Its findings could shape which bands proceed to a follow-on rulemaking. The FCC has not resolved the carriers' objections.

What happened to SpaceX's request?

The FCC rejected SpaceX's request to add the 902-928 MHz band to the proposed D2D rules. SpaceX argued that access would feed ongoing efforts to converge the capabilities of satellite and terrestrial networks.

The request was also viewed as a preemptive move against NextNav's separate case. NextNav has a petition seeking reconfiguration of its holdings for a terrestrial backup to GPS. SpaceX sought access before the FCC resolved that separate petition.

What does the auction vote change?

The FCC voted to advance a proposed future auction with four core parameters:

• Amount: The proposed future auction covers 25 MHz of midband spectrum.
• Bands: The frequencies are 1655-1695 MHz and 2020-2250 MHz.
• Uses: The FCC named terrestrial 5G, D2D, hybrid networks and potential 6G services.

The vote starts the proposed auction process but does not set final rules. It builds on the FCC's forthcoming auction of upper C-band spectrum, which the agency expects to complete by July 2027.

The 25 MHz plan links to a mandate to make up to 400 MHz of spectrum available for commercial use through auction by 2028. The FCC is separately exploring auctions in the 2.7 GHz and 7 GHz bands.

How could spectrum screens affect access?

The FCC's lone Democratic commissioner, Anna Gomez, advocates "spectrum screens" in both proceedings. The regulatory tool aims to prevent carriers from hoarding spectrum and keeping it beyond competitors' reach. Gomez said: "I worry about competition and making sure that everyone that wants to have access to spectrum, within reason, can get it."

Her intervention puts competition alongside technical coexistence. The FCC must decide how D2D access affects incumbent 5G operations and broader market entry. The current proposals do not define how a screen would operate or set final auction terms.

What happens next?

The FCC's votes do not propose any specific new rules. The agency expects to publish proposals for comment in the coming days. It will then set related comment and reply deadlines before taking further steps.

Upcoming steps include the final NTIA study, FCC comment and reply deadlines, and preparation for the proposed midband auction. The upper C-band auction must complete by July 2027, and the broader commercial-auction mandate runs to 2028. The next decisions will determine whether D2D enters the contested 5G bands and how quickly new midband supply reaches commercial operators.