Buyers Beware Ligado Spectrum

As the Federal Aviation Administration last week was determining how to keep 5G transmitter towers from interfering with aircraft navigation systems, Ligado Networks announced plans to market its spectrum through the brokerage and advisory firm Select Spectrum.

Caveat emptor, as the Romans used to say, or “let the buyer beware.” If America has learned anything this month, it’s been the following: Just because the FCC says it’s permitted, it doesn’t mean it’s ultimately permitted. The FCC does not always have the final word on spectrum usage.

Ligado Networks was given permission by the Federal Communications Commission in April 2020 to roll out a terrestrial network in spectrum next to bands reserved for global positioning services (GPS). This is the spectrum that Ligado is now trying to sell.

Wireless companies paid $94 billion to the U.S. Treasury and satellite companies for the right to use spectrum for 5G in the C-Band, between 3.7 and 3.98 GHz. But due to concerns from the FAA that the planned 5G transmitters would interfere with planes’ radio altimeters, AT&T and Verizon have cut back on power for deployments using the 3.7-3.8 GHz band around some airports through July 5, 2022.

The FAA has not yet announced its test results regarding interference with radio altimeters from wireless transmissions in the 3.8-4.0 GHz band, which is scheduled to be available in the next two years. There may yet be further delays and reductions in the usage of spectrum near large and small airports.

The same pattern of unanticipated carve-outs and delays from FAA concerns with the C-Band could be repeated by other federal agencies with Ligado spectrum when it is commercially developed. Some unsuspecting companies might buy the Ligado spectrum and think they were getting a good deal, but a federal agency can say no.

The Department of Transportation’s warnings of safety concerns to aircraft from 5G operations in the C-Band did not go into the official FCC docket, so AT&T, T-Mobile, and Verizon were unaware of FAA concerns when they bid for C-band spectrum. With more transparency, companies might have spent less. However, potential Ligado spectrum purchasers have ample notice that executive branch agencies and members of Congress are concerned about effects on GPS from use of Ligado terrestrial spectrum.

The first warning to potential purchasers of Ligado spectrum came on May 22, 2020, when the National Telecommunications and Information Administration, on behalf of the entire executive branch, filed a petition for reconsideration to the Federal Communications Commission, asking that the FCC rescind approval of the license modification granted to Ligado. NTIA stated that the license modification “will cause irreparable harms to federal government users of the Global Positioning System.”

The second warning came on June 22, 2021, when Senators Jim Inhofe (R-OK), Tammy Duckworth (D-IL), and Mike Rounds (R-SD) introduced a bill to require Ligado to pay private companies the cost of replacing or repairing GPS devices that were harmed by its operations. In the FCC Ligado Order, Ligado had to repay the federal government for public equipment that was harmed, but not privately-owned equipment.

Interference may occur because Ligado’s signals will be two billion times as powerful as received GPS signals. Ligado’s signals could interfere not only with navigation devices on general aviation and helicopters, but also with navigation systems in emergency vehicles such as ambulances and fire trucks. According to the Space Based Positioning, Navigation, and Timing Advisory Board, which provides independent advice to the federal government, “virtually all receivers will be degraded if they are too close to a Ligado Transmitter.”

With Ligado 5G transmitters drowning out GPS signals, pipeline maintenance and systems operations would be affected. Plus, private pilots might find that navigation technology does not operate, athletes might find that their health trackers do not function, and firefighters might not be able to get to their destinations. GPS is also used for precision agriculture and construction, surveying, and the electrical grid.

Ligado’s investors are more likely to sell its spectrum to an existing carrier than to build an independent nationwide network.  According to many observers, Ligado was expected to sell its spectrum to Verizon. However, with the company’s recent press release about Select Spectrum, Ligado may be seeking other suitors.

Harbinger Capital Partners, Ligado’s investors, spent $3.3 million on lobbyists in the first three quarters of 2021. But even these lobbyists can’t defeat the laws of physics and prevent Ligado from degrading GPS and harming navigation systems. What we’ve seen over the past month is that the FAA won’t sit idly by and let that happen, and other federal agencies may follow suit to protect GPS.