When Public Safety Isn’t Enough: FCC Considering Expanded Use of the 4.9 GHz Band

At its March Open Meeting, the FCC adopted a long-awaited Sixth Further Notice of Proposed Rulemaking (“FNPRM”) to consider promoting additional investment and activity in the 4.9 GHz band while preserving the core public safety purpose of the band. Finding the band underutilized by public safety users, the FNPRM invites comment on ways that the band might be more heavily utilized by public safety while entertaining several options by which others might gain access to the band on a shared basis, including those supporting Critical Infrastructure Industries (“CII”), Unmanned Aircraft Systems (“UAS”), and 5G networks. To implement any sharing scheme, the Commission proposes to draw upon previous experience in other bands, such as TV white spaces.


In 2002, the Commission designated 50 megahertz of spectrum (4940-4990 MHz) in for use by public safety services. The current band plan divides the band into ten one-megahertz channels (Channels 1-5 and 14-18) and eight five megahertz channels (Channels 6-13), while limiting channel aggregation bandwidth to 20 megahertz.

Although nearly 90,000 public safety entities are eligible for licenses in this band, the FCC’s licensing database reveals that fewer than 3,200 licenses have been granted. Given that only 3.5% of the eligible organizations making use of the spectrum, the Commission is concerned that the band has fallen short of its full potential.” Accordingly, the Commission seeks comment on alternative ways to foster increased usage of the 4.9 GHz band. The options integrated in the FNPRM draw on an extensive record as well as the National Public Safety Telecommunications Council (“NPSTC”) Plan generated in 2013 and the Association of Public Safety Communications Officials (“APCO”) Report submitted into the record in 2015.

Band Aggregation Proposals

At the outset, the FNPRM proposes to grandfather all incumbent users of the 4.9 GHz band as of the date final rules become effective. Beyond this proposal, the FNPRM focuses on possible expansion of public safety use of the band by relaxing in-band aggregation limits. The Commission seeks to retain the band’s existing channelization plan, but to increase the channel aggregation bandwidth limit 100% from 20 to 40 megahertz. The Commission also proposes to aggregate Channels 1-5 (1 MHz each) to form a five-megahertz bandwidth channel designated for aeronautical mobile and robotic use. The agency proposes to limit aeronautical mobile use to manned aircraft video payload operations (not allowing command and control), but also seeks comment on the potential for the 4.9 GHz band to support various UAS payload operations in the future. In addition, the FCC set forth a possible plan to accord primary status for public safety narrowband fixed point-to-point and point-to-multipoint links on Channels 14-18 (each is a 1 MHz channel). Currently, such narrowband links remain secondary to other public safety operations in the band.

Coordination Process Reforms and Spectrum Sharing

Per the FNPRM, the FCC solicits comment on requiring applicants for new stations and current licensees seeking modifications to submit to frequency coordination administered by FCC-certified frequency coordinators. The Commission proposes to use the Universal Licensing System (“ULS”) as the frequency coordination database for the 4.9 GHz band, and intends to use existing form schedules to capture point-to-point, point-to-multipoint, fixed receiver, base station, and mobile station data to populate the database. Under the FCC’s proposal, grandfathered incumbent 4.9 GHz licensees will not have to submit to frequency coordination for their existing operations in the band. However, incumbent licensees with point-to-point, point-to-multipoint, base, and mobile stations will still be required to file certain technical information in ULS to ensure their operations are protected during future coordination.

In the event the Commission expands eligibility to other classes of users, the FCC invites comment on the prospects of utilizing a two-tiered spectrum sharing framework. Under such a plan, the Commission proposes that public safety users would enjoy priority access and other users would gain access on a secondary or non-interfering basis. The Commission seeks comment on implementing such a structure by either utilizing the ULS database in a manner akin to the TV white spaces database or developing an automated database with potentially more robust capabilities to assure real-time protection of mission-critical public safety operations. The FNPRM does not explicitly propose using Spectrum Access Systems (“SAS”) or Environmental Sensing Capabilities (“ESC”), but asks questions which might implicate these or similar solutions.

Band Eligibility and Alternative Uses

In the FNPRM, the FCC solicits comment on a variety of ways to expand license eligibility in the 4.9 GHz band beyond public safety. Currently, only entities providing public safety services are eligible for licenses in the band. The FCC seeks comment on expanding eligibility by allowing entities from Critical Infrastructure Industries (“CII”) to operate in the band on a co-primary basis with public safety services (under the FCC’s rules, CII means State, local government and nongovernment entities, including utilities, railroads, metropolitan transit systems, pipelines, private ambulances, volunteer fire departments, and not-for-profit organizations that offer emergency road services, providing private internal radio services provided these private internal radio services are used to protect safety of life, health, or property; and are not made commercially available to the public.”).

Alternatively, the Commission seeks comment on whether it should redesignate the 4.9 GHz band, in whole or in part, for commercial wireless use (including potentially relocating incumbent public safety users to other frequency bands). In conjunction with possible expansion of eligibility, the Commission also seeks comment on ways to liberalize the terms on which public safety entities may lease 4.9 GHz spectrum to other parties eligible to operate in the band.


While the FNPRM largely focuses on channel aggregation and coordination process reforms to facilitate expanded public safety investment and use on a protected basis, this proceeding presents CII enterprises and various commercial wireless stakeholders with an opportunity to potentially gain access to valuable mid-band spectrum. Public utilities, non-public safety government organizations responsible for critical infrastructure, mobile carriers, and others are likely to be interested, as this is the only range of mid-band spectrum in the 4 GHz band currently under active consideration by the Commission in a rulemaking, although the agency is examining the 3.7-4.2 GHz band in the Mid-Band Spectrum Notice of Inquiry. However, the Inquiry proceeding cannot proceed directly to rules, and will itself require a rulemaking proceeding to be initiated before rules can be adopted.

Comments on the FNPRM will be due 60 days and reply comments will be due 90 days after publication of the FNPRM in the Federal Register. Publication has not yet occurred.