Broadcasters push back on satellite spectrum sharing changes as FCC weighs modernization

The broadcast industry is mounting resistance to proposed changes in how satellites share spectrum, warning that modifications to current interference protection standards could disrupt critical services used by television and radio stations nationwide.

The National Association of Broadcasters, DirecTV and satellite operator SES filed detailed comments with the Federal Communications Commission opposing or seeking limitations on elements of a rulemaking that would alter how non-geostationary satellite orbit (NGSO) systems like SpaceX’s Starlink share spectrum with traditional geostationary orbit (GSO) satellites in key frequency bands.

At stake are the Ku-band frequencies (10.7-12.7 GHz) that broadcasters increasingly rely on as the FCC reallocates portions of C-band spectrum for wireless broadband use.

NAB argues that at least 21 major broadcast licensees hold licenses in the Ku downlink band, with that number likely to grow as broadcasters seek alternatives to C-band services.

“Radio and television broadcasters depend on reliable GSO operations, and it is critical that their operations have primacy in the case of interference,” NAB stated in its reply comments filed Aug. 27. The trade group represents local radio and television stations nationwide.

The FCC’s notice of proposed rulemaking, released in April, seeks to “modernize spectrum sharing” between NGSO constellations and GSO satellites across multiple frequency bands.

NGSO operators have argued that current equivalent power flux-density (EPFD) limits constrain their operations, though SpaceX’s Starlink already serves more than 6 million customers globally, including over 2 million in the United States.

DirecTV, which provides satellite television to millions of subscribers, commissioned technical analysis showing significant service degradation under proposed changes.

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The company’s study found that reducing arc avoidance requirements for NGSO systems from 18 degrees to 4 degrees would increase service unavailability by 44.5% in Ku-band and 68.2% in Ka-band for a typical customer in Portland, Oregon.

“The existing framework that relies on the International Telecommunication Union’s equivalent power flux-density limits satisfies all of these requirements,” DirecTV stated in comments filed July 28. “Modifications to this framework would open GSO networks to substantial risk of harmful interference.”

The technical dispute centers on how to protect established satellite services while accommodating new mega-constellations.

GSO satellites operate in fixed positions roughly 22,300 miles above Earth’s equator, providing stable coverage areas but lacking the flexibility to avoid interference. NGSO systems like Starlink use thousands of lower-orbit satellites that move across the sky, offering more dynamic interference mitigation options.

NAB emphasized that broadcast systems cannot use adaptive coding and modulation (ACM) techniques to mitigate interference because they involve one-way transmissions to potentially hundreds of receive sites. When interference occurs, broadcast signals simply fail rather than adapting to maintain service.

“The ACM shift to a more robust MODCOD mode will always be adverse because the leased bandwidth available on the GSO satellite is fixed,” NAB explained, referencing the Shannon-Hartley theorem that governs information transmission limits.

The broadcast industry faces additional pressure from ongoing C-band transitions that will force some operators to migrate services to Ku-band frequencies. The FCC auctioned 100 MHz of C-band spectrum to wireless carriers for $81 billion in 2021, requiring satellite operators to vacate lower portions of the band. President Trump’s One Big Beautiful Bill Act now requires the FCC to auction at least another 100 MHz of Upper C-band spectrum by July 2027, likely pushing more broadcast services toward Ku-band alternatives.

“Any degradation of the Ku-band GSO interference environment would complicate a migration of high-reliability GSO services from the Upper C-band to the Ku-band,” satellite operator SES warned in comments filed July 28. The Luxembourg-based company operates more than 60 Ku- and Ka-band GSO satellites and 30 NGSO satellites, giving it perspective on both sides of the spectrum sharing debate.

Unlike NAB and DirecTV’s blanket opposition, SES offered a more nuanced position, arguing that Ku-band protections should remain intact while Ka-band limits could potentially be adjusted. The company noted that Ka-band EPFD limits were set in 2000 before any commercial Ka-band satellites were operational, while Ku-band was already an established broadcast distribution medium.

Both NAB and DirecTV urged the FCC to await completion of International Telecommunication Union studies before making unilateral changes to spectrum sharing rules. At the 2023 World Radiocommunication Conference, countries agreed to study EPFD limits with results submitted to the 2027 conference “without regulatory consequences.”

SES emphasized that unilateral U.S. action would create operational complications for satellite operators worldwide, particularly near borders where systems must simultaneously comply with different national rules. “If the U.S. and international rules were to diverge, an NGSO satellite serving a U.S. end-user near the U.S. border would be subject to the Commission’s rules but would be subject to the ITU EPFD limits for the protection of GSO end-users across the U.S. border,” the company explained.

“Technical analyses and policy discussions at the ITU are already well underway, and the FCC should view this activity as an opportunity to drive consensus internationally — not to diverge from it,” NAB argued.

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The comments reveal tensions between established satellite services and new broadband constellations as both sectors compete for spectrum access. While NGSO operators seek regulatory flexibility to expand services, traditional broadcasters warn that changes could undermine reliable program distribution that viewers expect.

The FCC has not indicated when it might act on the proposed rule changes. The commission continues accepting comments on the complex technical and policy issues involved in modernizing satellite spectrum sharing.