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T-Mobile: AST SpaceMobile Satellites Pose Potential Risk to Cellular Networks

T-Mobile tells the Federal Communications Commission that AST SpaceMobile needs to provide more details about how its satellite system will prevent radio interference.

 & Michael Kan Principal Reporter

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(Credit: AST SpaceMobile)

SpaceX's partner, T-Mobile, is pressing US regulators to scrutinize AST SpaceMobile, arguing that the company’s satellites risk causing harmful interference to terrestrial cell networks.

On Tuesday, T-Mobile sent a letter to the Federal Communications Commission, which is reviewing AST SpaceMobile’s application to operate a satellite internet service for phones. It urges the FCC to "take no action" on AST's application "unless and until sufficient information is provided” about the radio interference concerns. 

“AST has failed to demonstrate that its proposed SCS [Supplemental Coverage from Space] operations will satisfy the Commission’s stated goal to minimize the risk of interference from SCS services to existing terrestrial networks,” the carrier says.  

T-Mobile adds that AST should be required to disclose its maps detailing where the satellite signals will reach in the US, including over traditional cellular sites. 

“Accordingly, AST must provide maps that show the overlay of its satellite beams on all geographic market areas, for all relevant elevation angles, including license areas to which it will have access to terrestrial spectrum, and how its satellites will be capable of confining SCS service to those licensed areas,” T-Mobile claims. 

It also alleges that AST has been using metrics to underestimate the potential radio interference to user equipment. 

(Photo Illustration by Thomas Fuller/SOPA Images/LightRocket via Getty Images)

Texas-based AST SpaceMobile didn’t immediately respond to a request for comment. But the company’s upcoming constellation is poised to compete with SpaceX’s cellular Starlink, which launched through T-Mobile in July. 

AST has partnered with AT&T and Verizon to deliver its own satellite-to-phone service, starting as soon as next year. To do so, the company is preparing to launch dozens of exceptionally large "BlueBird" satellites, with the first prototypes scheduled to fly in the coming weeks. But another crucial step is receiving FCC approval to officially operate the satellite-to-phone service in the US. 

The radio interference concerns from T-Mobile are a bit ironic, considering its partner SpaceX has faced and fought back against its own interference claims from other companies. Such disputes are nothing new at the FCC, where satellite operators routinely lobby for spectrum access and regulatory approvals. 

SpaceX previously challenged AST’s plans through earlier FCC filings. However, AST has fired back, calling out SpaceX as anticompetitive and criticizing its approach to satellites.

About Our Expert

Michael Kan

Michael Kan

Principal Reporter

My Experience

I've been a journalist for over 15 years. I got my start as a schools and cities reporter in Kansas City and joined PCMag in 2017, where I cover satellite internet services, cybersecurity, PC hardware, and more. I'm currently based in San Francisco, but previously spent over five years in China, covering the country's technology sector.

Since 2020, I've covered the launch and explosive growth of SpaceX's Starlink satellite internet service, writing 600+ stories on availability and feature launches, but also the regulatory battles over the expansion of satellite constellations, fights with rival providers like AST SpaceMobile and Amazon, and the effort to expand into satellite-based mobile service. I've combed through FCC filings for the latest news and driven to remote corners of California to test Starlink's cellular service.

I also cover cyber threats, from ransomware gangs to the emergence of AI-based malware. In 2024 and 2025, the FTC forced Avast to pay consumers $16.5 million for secretly harvesting and selling their personal information to third-party clients, as revealed in my joint investigation with Motherboard.

I also cover the PC graphics card market. Pandemic-era shortages led me to camp out in front of a Best Buy to get an RTX 3000. I'm now following how the AI-driven memory shortage is impacting the entire consumer electronics market. I'm always eager to learn more, so please jump in the comments with feedback and send me tips.

The Best Tech I've Had:

  • My first video game console: a Nintendo Famicom
  • I loved my Sega Saturn despite PlayStation's popularity.
  • The iPod Video I received as a gift in college
  • Xbox 360 FTW
  • The Galaxy Nexus was the first smartphone I was proud to own.
  • The PC desktop I built in 2013, which still works to this day.

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