Public Safety Incumbents Want 4.9 GHz Band Expanded to Energy Industry Over Unlicensed

Incumbent public safety users of the 4.9 GHz band don’t agree with wireless advocates about expanding the band to unlicensed use or coordinating spectrum sharing, said comments filed by Monday’s deadline in docket 07-100. Allowing unlicensed use would ensure the most use “from the broadest set of stakeholders,” said the New America Foundation’s Open Technology Institute. Sharing the band should be handled carefully because public safety can't go anywhere else, public safety groups said. “What alternative spectrum has been made available?” asked the National Public Safety Telecommunications Council. “To NPSTC’s knowledge, none has been identified.”

Public safety users could share the 4.9 GHz band with unlicensed users through a tiered sharing system, said Dynamic Spectrum Alliance and OTI. The band suffers from low use and a “limited ecosystem” that increases the costs to use it, the alliance said. The use of automated spectrum sharing coordination in the Citizens Broadband Radio Service band “should be sufficient to overcome any misgivings” about interference with public safety operations, said the Wireless ISP Association.

Several public safety entities expressed concern about spectrum sharing coordination being handled by a third party or any non-public safety or governmental entity. “Public safety spectrum bands are not the appropriate arena to deploy new, unproven spectrum sharing methods,” said the Association of Public-Safety Communications Officials-International.

Numerous public safety entities said they're open to sharing the 4.9 GHz band, but with critical infrastructure industries (CII) such as energy companies rather than unlicensed users. “The potentially large number of unlicensed devices” would “raise the radio-frequency noise floor in a manner that would degrade public safety’s signal,” said the Public Safety Spectrum Alliance. “There is a natural alignment between CII and public safety in preparation and response to certain natural and man-made disasters,” said NPSTC.

Energy industry entities such as the American Petroleum Institute and the Energy Telecommunications and Electrical Association -- in joint comments -- also urged the FCC to allow CII sharing of the 4.9 GHz band. Sharing with CII users “could be the most administratively efficient way to increase use of the 4.9 GHz band and lower equipment costs for public safety incumbents,” said Florida Power & Light.

The energy industry commenters and some public safety entities also said the FCC should open up the band for use by public safety and energy industry drones and robotics. RF interference with drones can be more easily mitigated with a larger pool of channels, so the FCC should divide the 4.9 GHz band into sub-bands for legacy and new uses, said the API and the ETEA. Aeronautical users of the band transmitting signals to the ground “is the worst-case scenario” for potential interference with radio observatories, said the National Academy of Sciences’ Committee on Radio Frequencies.

The energy entities said CII users should have co-primary status with public safety in the band, but every public safety entity disagreed, saying public safety should be primary. Secondary use should be “fully pre-emptable,” said the Public Safety Alliance.