To 95 GHz, And Beyond!
The FCC adopted a new regulatory framework intended to enable experimental use of frequencies above 95 GHz. The recently-adopted First Report and Order in the Spectrum Horizons proceeding sets up a new category of experimental licenses—called “Spectrum Horizons Licenses”—for operations between 95 GHz and 3 THz. It also identifies 21.2 gigahertz of spectrum between 116 GHz and 246 GHz for unlicensed use. Access to these frequencies will be available on a non-interference basis for both experimental-licensed and unlicensed use operations. Commercial users must therefore coordinate with federal users, including those using passive services to support scientific research.
The Commission hopes to encourage investment in these short-wave bands through flexible licensing rules. The agency will issue Spectrum Horizons Licenses on a non-exclusive basis over any geographic area including on a nationwide basis. And they will be valid for a 10-year period rather than a 2- or 5-year period typically available for experimental licenses. Licensees can also transfer their Spectrum Horizons Licenses and market experimental equipment directly to the public.
The FCC also earmarked 21.2 gigahertz of spectrum (up from 15.2 gigahertz proposed in the Notice of Proposed Rulemaking) for unlicensed use in the 116-123 GHz, 174.8-182 GHz, 185-190 GHz, and 244-246 GHz band segments. Technical requirements for unlicensed use are much like those provided in Part 15 of the FCC’s rules for unlicensed operations in the 57-71 GHz bands. This includes power limit and out-of-band emission limit requirements.
Proposals in the Notice of Proposed Rulemaking on exclusive-use licensing remain pending, in response to commenters’ concerns. The FCC sought feedback, for example, on proposed rules to enable fixed point-to-point operations in frequencies between 95 GHz and 3 THz and whether these frequencies could benefit mobile operations. Several commenters cautioned that premature adoption of service rules could undermine technological innovation in these frequencies. Although deferring consideration, the FCC noted that it views these frequencies as “potentially suitable for licensed use.”
Those developing next generation services in these frequencies should remain engaged, as the FCC may resume efforts to adopt exclusive-use licensing proposals down the road. Frequencies between 95 GHz and 275 GHz are allocated for a myriad of operations, including fixed and mobile terrestrial services; fixed, mobile, and inter-satellite services; radiolocation, radionavigation, and radionavigation-satellite services; amateur radio; and various passive services. Pressure on the Commission to establish operating rules for one or more of these services will likely increase as industry advances make these extremely-high frequencies more suitable for commercial use.