IN Brief:
- The FCC published its proposed amendments to Part 15 ultra-wideband rules in the Federal Register on 2 November 2026.
- The consultation covers transmitter bandwidth definitions, normal-operation measurement procedures, and potential location-sensing device categories.
- Initial comments close on 2 December 2026, with replies due on 4 January 2027; existing rules remain in force.
The Federal Communications Commission has opened its formal consultation on revisions to US ultra-wideband (UWB) radio rules, with a 2 November 2026 Federal Register notice setting deadlines for technical submissions. The proposed changes cover the definition of a UWB transmitter, compliance measurement procedures, and restrictions on particular devices and applications. Initial comments are due on 2 December, followed by reply comments on 4 January 2027.
The consultation concerns Part 15, Subpart F of the Federal Communications Commission’s regulations, which allows qualifying low-power UWB devices to share spectrum with licensed services under specified limits. The original framework dates from 2002, when UWB equipment was primarily associated with particular radar, imaging, and communications applications. More recent systems employ waveforms, operating modes, and sensing methods that can be difficult to certify under definitions written for earlier transmitter designs.
UWB equipment spreads radio energy across a broad section of spectrum, typically at least 500MHz, allowing precise time-based ranging and short-range location measurements. Other systems analyse reflections to examine structures, detect movement, or map a space. The FCC is considering the way those capabilities are regulated in tracking, automation, automotive access, medical monitoring, and specialist radar equipment, while retaining protections for authorised spectrum users. The question is how to characterise transmitters whose frequency occupancy changes during normal operation.
One central proposal would remove the words “at any point in time” from the UWB transmitter definition. Current rules require the specified fractional bandwidth or at least 500MHz of bandwidth to be met instantaneously. A stepped-frequency or swept-frequency radio can cover a much larger range during a measurement cycle while occupying a narrower part of it at any given moment. The existing definition can therefore exclude a device from the UWB category even where its full transmission sequence provides the broad-band operation associated with UWB.
The FCC has granted waivers for some frequency-hopping, swept, and stepped systems, and is seeking evidence on whether revising the general rule would reduce the need for repeated individual exemptions. Its consultation explicitly asks for coexistence studies, including the consequences of concentrating transmission power into a narrower instantaneous bandwidth. Satellite navigation, radar altimeters, weather radar, and other incumbent services are among the protected systems that have to be considered when evaluating emissions, power spectral density, and signal timing.
A related issue lies in the test configuration. Existing provisions can require swept-frequency operation to be stopped at selected test frequencies, while pulse-gated devices may need to be measured with the transmitter held in its active state. Those procedures do not always represent the rapidly changing waveform used in service. The proposed approach would allow specified UWB equipment to be assessed in normal operation, making emission measurements more closely correspond to real transmitter behaviour while maintaining the requirement to demonstrate coexistence.
The Commission is also reviewing equipment categories and restrictions that currently separate ground-penetrating radar, through-wall imaging, indoor devices, and other defined uses. Modern location-sensing products have sometimes needed waivers to enter the market, leading the FCC to propose a new category for certain location-sensing applications. It is separately seeking comment on a possible category for AI-enabled UWB sensing. The document does not grant general permission for either class; the operating conditions and interference safeguards remain under consideration.
Radio hardware qualification requires evidence of the actual waveform, antenna configuration, radiated emissions, and test procedure used to establish compliance. A manufacturer developing a frequency-agile system would need to show how its chosen modulation and operating cycle meet any final requirements, including emissions in bands used by other services. Technical evidence submitted during the consultation may influence both the adopted definitions and the measurement practices used by certification laboratories.
The notice is identified as FCC 26-66 under ET Docket 26-245. The Commission adopted the proposal on 30 September and released it on 1 October; its Federal Register publication on 2 November established the formal consultation timetable. Existing Part 15 rules remain in force as the agency evaluates responses. The next material development will be the technical evidence filed by 2 December, followed by replies in January and the Commission’s subsequent rulemaking decision.
