Why Couldn't the FCC and FAA Solve Their 5G Problem?

• Author: Hazlett, Thomas W.

The United States is racing to deploy fifth generation (5G) cellular communications, and regulators may be proud of the progress made in allocating airwaves appropriate for the task. But a fight between the Federal Communications Commission and the Federal Aviation Administration threatens to eclipse the gains.

The backstory: In the summer of 2017, Intel and Intelsat asked the FCC to allow satellite systems to change radio use in "C-Band" frequencies between 3.7 and 4.2 GHz. In the 1950s, these airwaves had been licensed for long-distance telephone, and since the 1960s they had been shared with domestic and international firms to transmit video to cable TV operators. But the technologies supplying those services have changed significantly. Satellite operators saw an opportunity: invest in new systems to reduce their bandwidth requirements, and free up spectrum. They asked the FCC for permission to sell the new rights to mobile carriers, financing the transition.

Spectrum reallocation typically is a sixto 13-year process, as per the FCC's own calculations, but policymakers moved with uncharacteristic speed. The FCC evaluated the C-Band "re-harvesting," proposed new rules, and invited public comment.

In 2018, U.S. jetliner manufacturer Boeing told the agency that, to be cautious, it should leave a buffer of 100 MHz between the new SG transmissions and a band set aside for jetliner navigation. The FCC went further, allotting a 220 MHz "guard band."

In December 2020, the FCC launched Auction 107 for 5G rights, reassigning 280 MHz of the C-Band, between 3.7 to 3.98GHz. The auction closed in February of last year, with winning bids of $94 billion --the FCC's largest spectrum rights sale by a factor of two. Of the total, $81 billion was deposited in the U.S. Treasury, with $13 billion going to the incumbent satellite owners as compensation for clearing the band.

Wireless users would soon experience galloping speeds and superior networks, with U.S. tech leadership juiced. The C-Band reallocation had increased the availability of prime radio spectrum for mobile broadband by an impressive 36%. Verizon and AT&T, which had paid the lion's share of the money, were set to deploy their new capabilities last December.

The FAA steps in / But as the roll-out approached, the FAA began voicing concern that the new SG traffic could disrupt in-flight navigational systems, interfering with altimeters providing crucial data for bad-weather landings. Endangering...