FCC Seeks Comment on Direct-To-Device Satellite Use of Unlicensed Spectrum
Key Takeaways
- The NPRM proposes new mobile-satellite service (MSS) Earth-to-space allocations in the 2.400-2.4835 GHz (2.4 GHz) and 5.725-5.850 GHz (5.8 GHz) bands for operations on an unprotected, non-interference basis, while generally relying on existing Part 15 technical limits for user devices.
- The NPRM seeks comment on whether satellite downlinks should be authorized in the 5.8 GHz band or other bands currently available for Part 15 operations and, if so, what technical safeguards would be required.
- The Commission is considering multiple approaches, including license-by-rule and blanket licensing models to authorize D2D operations.
- The FCC proposes to clarify that Part 15 devices may be used aboard authorized spacecraft and seeks comment on broader space-based applications, including extravehicular activities (EVA), communications between spacecraft, and in-space servicing, assembly, and manufacturing (ISAM) operations.
- Companies with interests in D2D operations, emergent space industries, Wi-Fi, internet of things (IoT), or other unlicensed technologies should consider whether to participate in this proceeding.
Proposal to Authorize Earth-to-Space Satellite Operations in the 2.4 GHz and 5.8 GHz Bands
The NPRM proposes to add new MSS Earth-to-space allocations in the 2.4 GHz and 5.8 GHz bands via a new footnote in the U.S. Table of Frequency Allocations. The proposed allocations would permit satellite uplink operations in these bands on an unprotected and non-interference basis, subject to the FCC's rules. The FCC frames the proposal as a way to streamline the rules to facilitate the introduction of innovative D2D services and products.
The FCC also seeks comment on several related allocation issues, including whether satellite downlinks could be accommodated in the 5.8 GHz band, whether additional unlicensed bands may be suitable for future satellite operations, and whether any new allocations should support inter-satellite communications. The Commission also seeks comment on the appropriate regulatory status of such operations, including whether future users should be required to operate on a non-interference basis and how to address coexistence issues with licensed operators in the affected spectrum bands.
Exploring Satellite Downlinks in Unlicensed Spectrum: Interference and Coexistence Issues
The Commission takes a more cautious approach toward the authorization of satellite downlinks in spectrum available for Part 15 operations, opting to seek comment on a range of topics related to such operations rather than proposing to authorize them as part of the NPRM. The NPRM notes that a satellite downlink can illuminate a much larger geographic area than an individual terrestrial device, increasing the potential for harmful interference to authorized operations or adversely impacting large numbers of Wi Fi, IoT, and other Part 15 users simultaneously. The Commission, therefore, seeks comment on whether D2D satellite downlinks can coexist with existing licensed and unlicensed operations in unlicensed bands and, if so, what technical safeguards may be required.
The FCC specifically seeks comment on whether satellite downlinks could be accommodated in the 5.8 GHz band, which today supports a wide range of unlicensed operations. The Commission suggests the band may be a useful starting point because its higher frequencies permit smaller, more directional satellite antennas that could help limit the size of on-the-ground satellite beam footprints. At the same time, the FCC recognizes that any downlink framework would need to coexist with existing licensed and unlicensed users and therefore seeks comment on the technical and regulatory conditions under which such operations could be permitted.
The NPRM also asks whether other spectrum bands that currently support unlicensed operations, including additional frequencies in the 5 GHz and 6 GHz bands, could be used for future D2D operations.
Authorization Frameworks for D2D Operations in Unlicensed Spectrum
While Part 15 contains requirements for terrestrial devices that can be operated without an individual FCC license, the Commission must determine how best to authorize such devices to communicate with satellites consistent with the Commission's rules, including Part 25. The NPRM therefore seeks comment on the appropriate regulatory treatment for both the terrestrial and satellite components of these operations as well as potential rule changes to facilitate D2D operations.
Authorization of Terrestrial Devices
Although the NPRM generally proposes to rely on existing Part 15 technical rules, the Commission asks whether additional licensing or authorization mechanisms are necessary because the devices would communicate with satellite systems rather than exclusively terrestrial facilities. The NPRM seeks comment on several potential frameworks:
- License-by-Rule. The NPRM asks whether a license-by-rule framework, similar to the approach used in its Supplemental Coverage from Space (SCS) framework, would provide sufficient regulatory oversight while avoiding the administrative burden of individual earth station licensing.
- Blanket Licensing. The Commission also seeks comment on whether it would be more appropriate to adopt a blanket licensing framework under Part 25 of the Commission's rules for devices certified under Part 15 to communicate with satellites in one of the designated bands.
- Alternative Frameworks. The NPRM also seeks comment on whether the Commission should consider alternate licensing and sharing frameworks, including fully licensed approaches, alternative secondary or opportunistic frameworks, hybrid Part 15/Part 25 approaches, or any other framework that could accelerate investment and deployment for D2D.
Authorization of Satellite Systems
Participating satellite systems would remain subject to the Commission's satellite licensing regime. The NPRM seeks comment on three potential authorization frameworks, all premised on operations occurring on an unprotected, non-interference basis:
- Part 25 Licensing Following the SCS Model. As its primary inquiry, the Commission seeks comment on authorizing space stations under the existing Part 25 rules, following the general framework used for SCS. The NPRM seeks comment on related implementation questions, including the applicable processing and service rules, any required certifications or demonstrations of technical compliance, and whether milestones, bonds, or performance requirements should apply to satellites operating solely in the designated bands.
- License-by-Rule for Space Stations. As an alternative, the Commission asks whether certain operations (e.g., receive-only operations that use separately licensed bands for downlinks) could be authorized by rule, without an individual space station license.
- Permitted Space Station List. The Commission also seeks comment on whether it could maintain a list, similar to its existing "Permitted Space Station List," identifying satellites authorized to operate in the designated bands, with which license-by-rule user equipment could then communicate without further authorization.
Key Technical and Operational Issues
- Earth-to-Space. The Commission proposes maintaining the existing Part 15 power limits for devices transmitting to satellites and seeks comment on whether those limits, and other Part 15 technical rules, are appropriate for the proposed operations or whether they should be modified. Specific areas of inquiry include:
- whether the current power, antenna-gain, bandwidth, and out-of-band emission (OOBE) limits are sufficient for satellite communications;
- whether targeted modifications, such as higher power levels or antenna directivity requirements, would enable higher-value applications; and
- what measures could be used to protect sensitive incumbents, including radio astronomy and federal radiolocation operations.
- Space-to-Earth. The Commission seeks comment on the appropriate technical parameters for D2D satellite downlinks to enable new operations, protect authorized services, and facilitate coexistence with terrestrial Part 15 operations. Specific topics include:
- power flux density limits;
- satellite beam-size and geographic-coverage limits;
- aggregate interference limits addressing multiple satellite constellations;
- OOBE limits; and
- contention-based sharing mechanisms, such as listen-before-talk protocols.
Use of Part 15 Devices Within Spacecraft
The NPRM proposes to modify the FCC's Part 15 rules to clarify that such devices may be operated within spacecraft. The Commission tentatively concludes that permitting the use of common Part 15-authorized devices aboard spacecraft presents a low risk of harmful interference due to the distance from Earth and the shielding effects of spacecraft structures. The FCC also seeks comment on whether any conditions or limitations should apply to such operations, including whether the proposed clarification should extend to all Part 15 devices and all classes of authorized spacecraft, whether additional restrictions are necessary to protect terrestrial operations, and whether the rules should distinguish between intentional and unintentional radiators. The Commission further asks whether additional equipment restrictions, frequency limitations, or technical requirements may be appropriate for Part 15 devices used aboard spacecraft.
EVA, ISAM, and Communications Between Spacecraft
Beyond operations within spacecraft, the NPRM seeks comment on whether Part 15 technologies could support a broader range of space activities, including extravehicular activity, in-space servicing, assembly, and manufacturing applications, and other operations involving communications between spacecraft. The NPRM does not propose specific rules for these applications. Instead, it seeks comment on potential use cases, technical considerations, and whether existing Part 15 and satellite rules adequately accommodate EVA, ISAM, and spacecraft communications activities. These inquiries are thematically consistent with the FCC's recent inquiry into expanding spectrum access for emergent space operations.
Equipment Authorization
The NPRM seeks comment on whether existing Part 15 equipment authorization requirements are sufficient for devices that communicate with satellites or whether additional certification requirements should apply. In particular, the FCC asks whether satellite-enabled devices should be subject to any Part 25 equipment authorization requirements in addition to the certification framework that applies to terrestrial Part 15 devices today.
National Security and International Policy Considerations
The NPRM also devotes particular attention to a number of broader policy considerations, including the national security implications of extending satellite connectivity to devices operating under the FCC's Part 15 rules. While existing protections under the Secure and Trusted Communications Networks Act, the FCC's Covered List, and related equipment authorization restrictions would continue to apply, the Commission questions whether those measures are sufficient in a world where millions of unlicensed consumer, enterprise, and IoT devices may be capable of direct satellite communications. The FCC specifically seeks comment on whether:
- such operations could create new opportunities for cyber intrusion, state-sponsored espionage, or other malicious activities;
- certain devices, modules, manufacturers, or categories of equipment should be prohibited from communicating with satellites;
- any additional security, certification, or operational requirements should apply to satellite operators, equipment manufacturers, or service providers.
In the international coexistence context, the FCC acknowledges that the proposed satellite operations would not necessarily align with existing international spectrum allocations and seeks comment on how such operations could be accommodated under the International Telecommunication Union (ITU) framework. The FCC specifically notes that the proposed allocations would not conform to the ITU International Table of Frequency Allocations and seeks comment on what steps would be needed to ensure that any resulting frequency assignments do not cause harmful interference to, or claim protection from, stations operating in accordance with ITU requirements. The Commission also asks about the implications for international coordination, cross-border interference protection, and foreign-market access, particularly where other administrations have not adopted comparable rules.
Next Steps
The NPRM represents the FCC's first comprehensive effort to determine whether devices operating under the Part 15 rules can communicate with satellites at scale. Any company with interests in the deployment or use of D2D satellite technology, emergent space missions, Wi-Fi, IoT, or unlicensed technologies—including service providers, end users, and equipment manufacturers—should review the potential frameworks and proposed rules and consider submitting comments in response to this NPRM to help shape the outcome of the proceeding.
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Paul Powell is of counsel, and Heather Moelter is an associate in DWT's Portland office. Soraya Mohamed is an associate in the firm's Washington, D.C., office. DWT's communications and technology teams regularly advise clients on spectrum access and related regulatory issues. We are closely monitoring this proceeding and are available to assist companies in evaluating the potential impact of the FCC's proposals or preparing comments in this proceeding. For more information, please reach out to one of the authors or another member of our team. To stay informed, sign up for our alerts.