FCC Seeks Comment on Modernizing GSO and NGSO Satellite Spectrum Sharing (EPFD Limits)

Background: EPFD limits are technical rules that restrict the aggregate power that NGSO satellite constellations can direct toward GSO earth stations and satellites, protecting GSO systems from interference. The limits date from an era with far fewer and different NGSO systems. Large LEO broadband constellations argue that the limits constrain performance and capacity, while GSO operators emphasize the need for continued protection. In SB Docket No. 25-157 (published June 13, 2025), the FCC seeks comment on modernizing sharing in the 10.7-12.7 GHz, 17.3-18.6 GHz and 19.7-20.2 GHz bands where EPFD limits apply. Key provisions: The summary indicates a request for comment on modernizing the sharing framework, not a specific final rule. Possible questions include whether to revise or replace EPFD limits, how to measure aggregate interference, whether alternative protection criteria are appropriate, and how U.S. positions relate to international ITU rules, since EPFD limits originate in international regulations. The summary does not give the specific numeric proposals, so readers should read the full NPRM. Timeline: No comment deadline appears in the provided data, and the notice dates from mid-2025. Check ECFS for the status of the comment cycle and any later actions. Any rule changes would come after Commission action, and international coordination could add time, particularly if ITU limits are involved. Implications: For NGSO operators, relaxed limits could allow higher power or more flexible operations, increasing capacity and lowering cost per bit. For GSO operators, relaxed limits could raise interference risk, degrade service quality or require operational changes, so they will seek strong safeguards. The outcome may also influence spectrum sharing among newer entrants and future filings. Because the affected bands are commonly used for broadband, broadcasting distribution and feeder links, changes could have commercial consequences across both segments. Operators should model how alternative limits would affect their link budgets, availability, and constellation design. Customers of GSO services, such as broadcasters and enterprise networks, may also have a stake. Because international rules are involved, the FCC's domestic changes could influence U.S. positions at future ITU conferences, and other administrations' reactions may affect global operations.