The U.S. Federal Communications Commission (FCC) has released a new Knowledge Database (KDB) publication titled
800303 D01 Sub-THz Emission Measurement Guidance v01, providing updated recommendations for measuring emissions from devices operating above 95 GHz.
The document offers practical guidance to manufacturers, test laboratories, and measurement professionals performing compliance evaluations on extremely high-frequency (EHF) devices. It addresses the need for consistent measurement methods in frequency ranges that extend beyond the limits covered by existing test standards such as ANSI C63.10-2020.
Purpose of the Guidance
The Sub-THz Emission Measurement Guidance establishes recommended procedures for measuring radiated emissions from equipment operating at frequencies above 95 GHz. Because existing FCC measurement procedures typically cover frequencies up to about 95 GHz, this publication provides additional direction for evaluating devices that exceed that range—ensuring that testing remains accurate and reproducible.
Scope and Application
According to the KDB, the guidance applies to measurements of unlicensed and licensed devices that fall under the FCC’s equipment authorization procedures and operate in the sub-terahertz (sub-THz) region.
It includes general information on:
Measurement environments suitable for frequencies above 95 GHz.
Equipment-under-test (EUT) configuration and test distance considerations.
Instrumentation and calibration needs when measuring radiated emissions at extremely high frequencies.
Procedural recommendations to supplement existing test methods where current standards do not provide explicit instructions.
The document does not create new regulatory limits or certification requirements.
Instead, it serves as supplementary measurement guidance to support compliance demonstrations under relevant FCC Parts 15 and 18 and other applicable rule sections.
Key Considerations Highlighted by the FCC
Measurements above 95 GHz require attention to setup geometry, alignment accuracy, and measurement system calibration due to the very short wavelengths involved.
Free-space loss, environmental effects, and instrumentation bandwidth can significantly influence results at these frequencies.
Laboratories should ensure that measurement uncertainty and repeatability are appropriately managed when extending their test capabilities into this frequency range.
Why This Matters
As technologies continue to evolve toward higher frequencies, including the sub-terahertz spectrum, reliable measurement guidance is essential for future product development and regulatory compliance. By publishing KDB 800303 D01, the FCC provides industry stakeholders with a consistent framework for performing accurate, traceable radiated-emission measurements above 95 GHz.
Access the official FCC document below: KDB Publication 800303 D01 Sub-THz Emission Measurement Guidance v01
Released by the Office of Engineering and Technology (OET), Federal Communications Commission, USA
At C-PRAV, we monitor global regulatory and measurement-standards updates to help manufacturers and laboratories stay informed about new compliance expectations across emerging technologies and frequency ranges.