The Federal Communications Commission has taken the next step toward its goal of providing operators of unmanned aircraft systems (UAS) access to protected and licensed spectrum, releasing a notice of proposed rulemaking (NPRM) that seeks comment on several proposed mechanisms and spectrum bands for UAS use. Specifically, the NPRM seeks comment on proposed service rules for UAS access to licensed spectrum in the 5030-5091 MHz band, on the adequacy and capability of utilizing terrestrial flexible-use networks for UAS operation, and on a proposed licensing mechanism for UAS communications in the aeronautical VHF band.

The FCC emphasized that it does not intend to require that all UAS use be confined to the 5030-5091 MHz band, but instead to make this band become a complement to other spectrum resources that may be available for UAS operations.

Comments will be due 30 days after the NPRM is published in the Federal Register, and reply comments will be due 60 days after Federal Register publication.

Proposed UAS Operations in the 5030-5091 MHz Band

The FCC proposes to adopt a band plan and service rules in the 5030-5091 MHz band enabling interference-protected UAS control-and-non-payload communications (CNPC) operations. The proposed band plan will partition the 5030-5091 MHz band into different segments for two broad use cases:

• Radio-line-of-sight operations (which the FCC will call “Non-Networked Access” or “NNA” operations) involving a direct wireless link between the UAS operator’s controller and the UA; and
• Beyond-radio-line-of-sight operations (which the FCC will call “Network-Supported Service” or “NSS” operations), which rely on deployed network infrastructure such as cell towers and sites to relay information between the operator and UA.

The FCC seeks comment on its proposed plan, including the size and placement of the spectrum blocks allocated for NNA and NSS operations, whether to make spectrum available for multi-purpose uses, any alternatives to the band plan, and any other use cases that should be considered in the band plan.

For directly-linked NNA operations, the FCC proposes to allocate at least 10 MHz of the available spectrum on a “license-by-rule” basis, meaning that the spectrum would be managed by one or more automated Dynamic Frequency Management Systems (DFMS), which would be administered by private third parties and modeled after the Spectrum Access System (SAS) adopted in the 3550-3700 MHz CBRS band. The DFMS would receive use requests from and temporarily assign frequencies to UAS operators for exclusive and protected use on a temporary basis and within a particular geographic area tailored to a submitted flight plan, enabling any UAS operator with a valid request to receive temporary exclusive access to the spectrum without needing to get an individual license from the FCC. The FCC seeks comment on its NNA proposal, the size and structure of the allocated NNA spectrum, and any requirements that should be placed on NNA operators and their requests for use. The FCC also seeks comment on the proposed DFMS system, including the DFMS selection and eligibility process, DFMS rights and responsibilities, and whether any other aspects of the CBRS band’s SAS approach could be adapted for NNA operations.

For network-based NSS operations, the FCC proposes to make the spectrum available through exclusive-use geographic area licensing and is requesting comment on the appropriate size for the geographic licensing areas and on how the licenses should be allocated (such as by auction or other means), and whether to make NSS spectrum available to NNA operations on an interim basis. In addition, the FCC is requesting comment on a number of detailed technical issues for both NNA and NSS operations.

UAS Operations in “Flexible Use” Bands

In response to the considerable interest in using existing terrestrial mobile networks for UAS communications, the FCC seeks comment on the adequacy of its current rules to ensure co-existence of existing terrestrial wireless networks and UAS, and on the regulatory solutions that may be necessary to facilitate and encourage such use. In addition, the FCC requests comment on:

• Any particular spectrum bands that might be utilized for UAS operations, and those bands that would not be suitable for such use; and

• Any interference concerns about UAS use of a particular band, and whether and what modifications to the FCC’s rules should be required to protect existing users and/or adjacent service areas and bands from harmful interference caused by UAS use.

The FCC urges commenters to provide information about the specific bands and UAS use cases they are interested in and to identify the type of technology or infrastructure needed to support such operations, and to provide technical studies and analyses regarding the potential for UAS operations to cause interference to adjacent channel, band, or market operations.

Licensing UAS Operators for VHF Operations

Finally, the FCC proposes to establish a mechanism for UAS operators to apply for an individual license in the VHF band (117.975 – 137 MHZ) as required by the Federal Aviation Administration (FAA) for air traffic control and advisory communications purposes. The FCC seeks comment on this proposal and on its tentative conclusion that ground stations for VHF communications should not be licensed by rule.