UAS at sunset

Sept. 9, 2020

The Federal Communications Commission (FCC) recently recommended a portion of C-band radio frequency spectrum be reserved for drone use and presented the recommendation to Congress in a report on Section 374 of the FAA Reauthorization Act of 2018.

View the FCC’s report.

The FCC study considered whether unmanned aircraft system (UAS) operations should be permitted on the 960-1164 MHz portion of the L-band and 5030-5091 MHz portion of the C-band. The commission did not recommend using the 960-1164 MHz portion of the L-band, which the report states is already “heavily encumbered with critical aeronautical navigation uses and presents, at best, a limited opportunity for UAS operations”.

“NBAA is supportive of the FCC’s efforts to provide unencumbered, consistent access to bands for UAS communications,” said Heidi Williams, NBAA’s director of air traffic services and infrastructure. “We are encouraged by FCC’s link to the work being done on standards development through RTCA and others, and we encourage the FCC to align its recommendations with those efforts.”

The FCC acknowledged the RTCA work, including the RTCA SC-228 Minimum Performance Standards for Unmanned Aircraft Systems, in the areas of line-of-sight and beyond-line-of-sight command-and-control operations as well as detect-and-avoid equipment to support UAS use in the 5030-5091 MHz band.

The FCC also suggested more evaluation of network-based UAS applications from mobile communications providers and others, which take advantage of flexible-use spectrum in other bands. The commission said these may be a low-cost and more immediately available option compared with building a dedicated UAS spectrum in 960-1164 MHz or 5030-5091 MHz bands. The rules related to these bands did not consider UAS use, so the commission recommended further study to ensure UAS communications do not cause harmful interference to other communications.

“The 5030- 5091 MHz band appears to offer promise for intensive UAS use because it is unencumbered, but that band poses some technical and regulatory issues that require further review before UAS operations may be permitted,” the report concludes, while further suggesting the FCC “engage with stakeholders to determine whether UAS flexible-use spectrum can support UAS operations without harmful impact or whether regulatory measures are necessary.”