Starlink gets FCC nod for space calls, but can't dial up full power

Authorization conditional on operations not causing harmful interference

Despite granting Starlink conditional authorization for direct-to-cell satellite-based phone services, the Federal Communications Commission (FCC) has deferred a request to operate at signal strengths beyond those allowed.

SpaceX's satellite operations biz can, according to the US comms regulator, operate its constellation of Gen2 satellites in the relevant frequency bands for what the FCC calls Supplemental Coverage from Space (SCS).

In Starlink's case, this means parts of the PCS G Block (1915 MHz for Earth-to-space and 1990-1995 MHz for space-to-Earth). This is spectrum allocated to T-Mobile US, Starlink's terrestrial cell network partner, with which it plans to operate its direct-to-cell service.

The authorization is conditional on SpaceX's SCS operations not causing harmful interference to other services operating in the relevant bands.

SpaceX and T-Mobile announced their agreement back in 2022, and Starlink started advertising its direct-to-cell service the following year, saying it expected to offer text messaging "starting in 2024," with voice and data capabilities added in 2025.

The idea of SCS is that Starlink will be able to provide a service to T-Mobile subscribers in parts of the US that are not covered by the telco's cell towers, effectively making the satellite operator a network roaming service for T-Mobile users. Coverage is to include the entire continental US, Alaska, Hawaii, and Puerto Rico.

FCC chair Jessica Rosenworcel said in a speech last month that integration of satellite and terrestrial networks would eliminate dead spots in network coverage, boasting that her agency was the first regulatory authority to put in place a policy framework to enable this.

It is understood this is the first such approval to operate a commercial SCS, although the FCC did temporarily allow SpaceX and T-Mobile to provide coverage for areas hit by Hurricane Helene last month. Other satellite providers such as AST SpaceMobile are also readying their own services.

However the FCC has deferred consideration of a request from SpaceX for a waiver on the aggregate out-of-band power flux density (PFD) limit of -120 dBW/m2/MHz on its SCS frequency emissions.

This power limit was imposed by the FCC itself as part of its policy framework in an effort to minimize interference between the signals from satellites and adjacent frequency bands used by other services.

SpaceX previously insisted that Starlink would not be able to successfully operate its planned direct-to-cell service unless it was allowed to exceed this limit, hence the request for a waiver.

The issue is the cause of a dispute between SpaceX and US telcos Verizon and AT&T, which both submitted documents to the FCC asking it to deny the waiver demand because it risks interference with existing cellphone services.

Verizon and AT&T teamed up with competing orbital operator AST SpaceMobile to provide direct-to-cell services to their own subscribers, leading SpaceX VP of Satellite Policy David Goldman to blast AST and its partners as "meme-stock" rivals carrying out a "scorched-Earth campaign to hamstring competing direct-to-cellular operations."

Gartner Distinguished VP Analyst Bill Ray previously told The Register that there are legitimate concerns about interference, but these were also being used in attempts to stifle competition.

"The issue is that no one has ever done this before, so no one knows how bad (or how benign) [interference] might be," Ray said.

It isn't clear if the FCC's decision not to allow a waiver on signal strength at this time will affect Starlink's plans to operate its direct-to-cell service. We asked SpaceX for comment.

In addition, the FCC also deferred SpaceX's request to deploy additional Gen2 Starlink satellites beyond the total of 7,500 satellites already authorized. The company wants to deploy a further 22,488 units, which includes those proposed to operate in the 340, 345, 350, and 360 km orbital shells.

SpaceX's CEO Elon Musk has been chosen by President-elect Trump to head up his Department of Government Efficiency (DOGE) after inauguration next year. ®