AST SpaceMobile Clears the FCC for Direct-to-Device — and the Interference Conditions Become the Battleground
The FCC's commercial grant lets satellites connect ordinary phones using mobile-carrier spectrum. But the authorization is fenced with power-flux-density limits and shutdown obligations — and that is exactly where the direct-to-device spectrum fight will be fought.
What happened
The FCC granted AST SpaceMobile commercial authority to operate a non-geostationary constellation and deliver direct-to-device cellular broadband from space, building on the agency's supplemental-coverage-from-space framework for connecting standard handsets to satellites using terrestrial mobile spectrum, in collaboration with AT&T, Verizon, and FirstNet. It is among the first major commercial grants of its kind in the United States.
The grant is conditional. AST must meet strict power-flux-density specifications, control beam shape and footprint, and cease operations on detection of harmful interference. T-Mobile and SpaceX — themselves pursuing direct-to-cell service — raised interference concerns during the proceeding. The FCC approved subject to conditions designed to protect incumbent terrestrial and satellite operators, which means the operative rules of the band now live in the license conditions, not the headline approval.
Why it matters for dispute formation
Direct-to-device reuses terrestrial mobile spectrum from orbit, so the dispute is structurally an interference dispute. The early signal is the condition set: power-flux-density limits, beam-management obligations, and the 'cease on harmful interference' trigger. Those conditions are the contract between operator and regulator — and the first place a competitor or incumbent will point when it claims its own service is being degraded. Who carries the burden of proving interference, and who must turn beams off, is decided in the license language before any signal is transmitted.
For spectrum, regulatory, and commercial teams, the work is to read the grant conditions as live obligations: map the power-flux-density and out-of-band-emission limits against your network, document compliance and any interference complaints, and align the satellite-and-carrier commercial agreements with the regulatory conditions so a single interference event is not litigated twice. As more D2D entrants are authorized in the same and adjacent bands, the conditions imposed on the first grant become the template — and the pressure point — for the next.
Who's exposed
Exposed as the grant holder operating under strict power-flux-density limits and an obligation to cease beams on detection of harmful interference — a license whose value turns on the interference conditions attached to it.
Exposed as the terrestrial partners whose licensed spectrum underpins the supplemental-coverage-from-space service; their network performance and authorization rights are entwined with the satellite operator's compliance.
Exposed as the competing direct-to-cell pairing that raised interference concerns in the proceeding; the conditions imposed on one entrant set the terms of the band for the next.
Exposed wherever supplemental coverage from space presses against neighboring licensees protected by power-flux-density and out-of-band-emission limits — the technical line where capacity meets interference law.
The historical parallel · Ligado / LightSquared vs GPS, Iridium and DoD (L-band interference)
Ligado's plan to use L-band spectrum for a terrestrial network drew years of interference objections from GPS users, the Department of Defense, and Iridium, culminating in a constrained FCC order and continuing disputes. It is the canonical lesson that a spectrum authorization is only as good as its interference conditions: the grant can issue and still be fought, narrowed, or stalled for years over harmful-interference claims. Direct-to-device reuses terrestrial bands from orbit — the same fault line, one altitude up.
What to watch
- How 'cease on harmful interference' is operationalized — who proves interference, on what threshold, and how fast beams must shut down.
- Competing direct-to-cell authorizations (Starlink/T-Mobile, Lynk) and whether the conditions imposed converge or diverge across operators.
- Power-flux-density and out-of-band-emission disputes with adjacent-band and incumbent licensees.
- Whether the FCC opens or revises a supplemental-coverage-from-space rulemaking that resets the conditions for all entrants.
Sources
See the disputes forming before the market does.
Signal Watch tracks the developments. The monthly Intelligence Brief synthesizes all four signals into the disputes most likely to crystallize next — free.
Get the Intelligence BriefFor general information only; not legal advice, and no attorney–client relationship is formed through this article. Company names appear because the companies are exposed to a public development — not as a statement of wrongdoing or a predicted outcome. Figures are as reported by the linked sources.