Satellite Operators Split on 17 GHz Downlink Allocation Timing

The 2023 World Radiocommunication Conference will consider opening up the 17 GHz band to non-geostationary orbit fixed satellite service downlinks, but the FCC doesn't have clear support among satellite operators about whether it should do so sooner, based on docket 22-273 replies Wednesday. Comments in December on an NGSO FSS downlink allocation in the 17.3-17.8 GHz band were also mixed (see 2212280016). No one has shown why the FCC would need to act before WRC-23 since the ITU is currently evaluating the feasibility of NGSO FSS use of the 17.3-17.7 GHz band segment in ITU Region 2, Viasat said. Also lacking are technical studies and quantitative and qualitative analyses of interference from and compatibility of NGSO operations in the band segment, it said. Hughes and DirecTV said the record shows support for an NGSO FSS allocation in the 17 GHz band, but on a secondary or unprotected basis, and after international adoption of the new allocation WRC-23. Primary access for NGSOs could preclude GSO networks altogether from the band since they have less flexibility in avoiding being the cause or recipient of harmful interference, they said. Amazon's Kuiper said the FCC needn't wait for adoption of a new primary allocation in Region 2 at WRC-23 because the agency "has often led the world [with spectrum allocations] ahead of international deliberations." It said its proposed technical rules to support sharing are backed "by concrete technical analysis." All the reasons the FCC gave for allowing GSO FSS operations in the band apply just as much for NGSO FSS operations there, SpaceX said: There's no reason to wait until after WRC-23, since all the relevant studies are done. Noting technical studies done in preparation for WRC-23, SES/O3b, Telesat and OneWeb said it's clear NGSO FSS services would be compatible with incumbent services in the band. It said the record supports the idea that NGSO FSS operations can share the 17 GHz band with geostationary broadcasting satellite service downlinks, direct broadcast satellite feeder links and with GSO FSS downlinks on a co-primary basis by extending the provisions applicable to NGSO systems in adjacent bands. AT&T and Verizon said Tuesday that advocates of opening the band to NGSO downlinks haven't shown there won't be harmful interference with incumbents. They said using ITU power flux density limits for adjacent-band FSS operations isn't enough because those PFD limits are outdated, based on fewer and much smaller NGSO constellations than are currently and soon-to-be authorized, and don't consider the potential for aggregate interference. In an International Bureau filing this week, Mangata urged FCC approval of its pending U.S. market access petition and related waivers, saying its planned use of the 17.7-17.8 GHz downlinks could be conditioned on the outcome of the pending 17 GHz NGSO rulemaking.