TAMPA, Fla. โ€” Ligado Networks faces renewed calls to block its terrestrial wireless plans over GPS interference concerns as the company prepares to turn part of its network on as early as Sept. 30.

Satellite operators Iridium, PlanetiQ and GeoOptics joined a group of 90 companies, organizations and associations hoping to overturn the regulatory approval Ligado secured two years ago for the network.

In letters addressed to U.S. President Joe Biden and Congress April 25, the group said more time is needed to assess how Ligadoโ€™s L-band spectrum could cause โ€œharmful interferenceโ€ with GPS technology.

They said Ligado is due to start using the spectrum before the Federal Communications Commission can review eight pending petitions from Iridium, the Air Line Pilots Association and others to reconsider its approval.

The group also highlighted how following FCC approval โ€œCongress mandated an independent technical review to further assess the harmful interference that would be caused by Ligadoโ€™s proposed network,โ€ and required the Department of Defense to brief federal representatives โ€œon the potential for widespread harmโ€ from the network.

โ€œOn this basis alone, the FCC should stay the Order to adequately consider the material new information that will be uncovered as a result of these ongoing Congressionally-mandated processes,โ€ the group wrote.

The FCC granted Ligado permission in April 2020 to use its satellite L-band spectrum terrestrially โ€” despite opposition from the Pentagon and other government agencies โ€” following a four-year proceeding.

The approval came with conditions including reduced power limits and a requirement that part of the spectrum be used as a โ€œguard bandโ€ near GPS and other adjacent operations.

In a March 31 regulatory filing, Ligado said it had reached out to federal agencies to obtain information on their GPS devices as required by its regulatory approval.

However, it said it had โ€œnot received information about a single device that the federal government believes needs to be repaired or replaced due to Ligadoโ€™s proposed operations.โ€

The company said the โ€œlack of communication suggests either that no government devices are affected or that the agencies are ignoring the [FCCโ€™s] directive.โ€

In the same filing, Ligado said it plans to start operations in the 1526โ€“1536 MHz band on or after Sept. 30 in parts of Virginia.

Other details about the services Ligado plans with these frequencies were not disclosed, and the company was unable to provide a comment before this article was published. 

Ligado has 35 MHz of L-band spectrum in total. 

Nokia has been developing 5G base station radios that will be compatible with Ligadoโ€™s spectrum for deploying private wireless network solutions for energy, manufacturing, health care, transportation and other infrastructure sectors.

Japan-based network operator Rakuten Mobile has also been working with Ligado to set up private wireless networks.

Jason Rainbow writes about satellite telecom, finance and commercial markets for SpaceNews. He has spent more than a decade covering the global space industry as a business journalist. Previously, he was Group Editor-in-Chief for Finance Information Group,...