Updated Ligado Networks, which is currently seeking approval for a terrestrial low-power 5G network, has won a powerful friend: Federal Communications Commission (FCC) chief Ajit Pai.

The US industry watchdog has circulated a draft letter asking individual FCC members to approve the firm's plans, with "stringent" conditions attached.

"After many years of consideration, it is time for the FCC to make a decision and bring this proceeding to a close," wrote Pai [PDF].

"We have compiled an extensive record, which confirms that it is in the public interest to grant Ligado's application while imposing stringent conditions to prevent harmful interference. The draft order that I have presented to my colleagues would make more efficient use of underused spectrum and promote the deployment of 5G and Internet of Things services."

This is despite vocal protests from the airline industry and the US Defense Department.

The biggest thorn in Ligado Networks' plans is its proposed use of the L-band spectrum, which the IEEE defines as ranging from 1Ghz to 2Ghz.

The L-Band is less susceptible to "rain fade," where signals are degraded by atmospheric rain, snow, and ice. It can easily penetrate cloud cover. And because they have low frequency ranges, a single antenna can cover longer distances.

Consequently, every satellite-based location technology — from the US GPS system, to Galileo, GLONASS, and BeiDou — uses the L-Band. And that's without mentioning the myriad of military uses for the spectrum.

There are fears that Ligado's nationwide 5G network could interfere with existing systems, particularly those used for aircraft navigation.

From the private sector, FedEx, Delta, Lockheed Martin, and JetBlue have all filed a petition seeking to dismiss Ligado Networks' proposal. If approved, this would force the firm to re-apply from scratch.

LightSquared shuffles away from GPS bands READ MORE

And on Wednesday, a bipartisan group of senators from the Armed Services Committee wrote to US prez Donald Trump, asking him to use stop the proposals from going forward.

"Ligado's planned usage will likely harm military capabilities, particularly for the U.S. Space Force, and have major impact on the national economy. Further, this plan would cost taxpayers billions of dollars to replace current GPS equipment, which could be rendered useless, and would force American families and businesses to use foreign space-based navigation and timing systems to replace the functions of GPS. This is fundamentally a bad deal for America’s national and economic security, and the timing could not be worse," they wrote.

Recon Analytics analyst Roger Entner has described the timing of the current move as being a "poisoned chalice" for Ligado itself, telling Light Reading that the company formerly known as LightSquared would need to raise some serious cash (possibly a big ask in the midst of the COVID-19 crisis) for buildout for its ostensible move to use the spectrum for industrial IoT services. Others speculate it could be pushed to sell its L-band holdings.

Ligado has adjusted its plans to limit any potential interference, with its application amended to reduce the power of its terrestrial base stations by 99.3 per cent. It also plans to use 23Mhz of spectrum as a "guard band" to protect neighbouring systems. But despite that, it's clear the military and airlines are yet to be convinced. ®

Updated to add

On Monday the FCC formally approved Ligado's application.