Incumbent Users Raise Concerns on 5G in 1675-1680 MHz

Comments come as FCC Chairman Brendan Carr calls for an aggressive spectrum agenda, making more frequencies available for 5G (see 2503030040).

NTIA submitted for the record its recent Spectrum Pipeline Reallocation Engineering Study, which was based on a lengthy NOAA examination and found sharing may be possible.

The AGU and others cited that study in their comments. “While we recognize the [NTIA] report noted that sharing may be ‘potentially feasible’ with commercial wireless carriers operating in uplink mode, we remind the FCC that for public forecasting operations to not be harmed, non-Federal users need protections as well to be able to accommodate such operations,” the AGU-led filing said. “While the mitigations necessary to address risks from satellite downlinks are very large, the protections required for uplink operations are, while still problematic, considerably smaller, leading to smaller exclusion zones of less than 60 km in size.”

The filing was also signed by the ALERT Users Group, American Meteorological Society, American Weather and Climate Industry Association, National Weather Association and University Corporation for Atmospheric Research, among others. They noted that those endorsing the group filing have raised concerns in more than 120 previous filings: “We submit that these comments remain fully relevant, and those views should continue to be considered as part of this proceeding.”

The U.S. Army Corps of Engineers (USACE) Water Management Community of Practice warned of the need to protect direct readout ground stations (DRGS) operating at 1679.9 MHz. Data collected through those systems provides “modeling, forecasting, inland and coastal navigation, daily operational decision support, flood and drought response, emergency response, flood inundation mapping, upward reporting, and public dissemination for the protection of life, property, and critical infrastructure,” the filing said. Any recommendation “that exposes the USACE DRGS infrastructure to 5G, LTE or other interference, or employs a less reliable or more latent distribution model would imperil the USACE mission and is considered non-viable under any circumstances.”

The Working Group for Satellite Telemetry raised similar concerns. The geostationary operational environmental satellite data collection system “relay[s] millions of hydrological, meteorological, oceanic, and weather observations transmitted from 30,000 data collection platforms each day,” the working group said: “The reliability of these ... systems cannot be overstated and is evidenced by their continued use even with [the] advent and evolution of high availability, cloud computing and satellite internet.”

But Ligado said the NTIA report was based on “years of comprehensive study” and confirms “that federal-commercial sharing in the band is feasible” with protections. Ligado noted that it first sought reallocation of the spectrum in 2012, citing “its nationwide scope and minimal utilization.” The final report finds that “with appropriate safeguards, ‘users could primarily rely on other data acquisition means (e.g., terrestrial) and commercial users could be granted full access to the band,’” Ligado said. The company “agrees with these views and looks forward to working with NOAA, NTIA, and the Commission to implement these mitigation measures.”

EchoStar said if the band is repurposed for 5G, it should be sold through an FCC auction, if Congress restores the agency’s general auction authority. “The general competitive bidding rules and a standard auction format are time-tested and will provide the simplest way to disseminate licenses in the 1675-1680 MHz band while recovering a portion of the proceeds for the U.S. Treasury,” it said.