WASHINGTON — A bipartisan group of senators — led by the chairman and top Republican on the Armed Services Committee — is urging the Federal Communications Commission to overturn a two-year-old decision establishing a new 5G network the lawmakers say could interfere with GPS.

The bipartisan push against Ligado Networks comes as the company prepares to launch its terrestrial wireless network as soon as October. The FCC in 2020 granted Ligado’s application to do so.

Chairman Jack Reed, D-R.I., and ranking member James Inhofe, R-Okla., and six other bipartisan senators have sent a letter to FCC Chairwoman Jessica Rosenworcel and her fellow commissioners asking they “stay and reconsider the FCC’s order granting the applications” for Ligado to deploy its wireless network using the same L-band frequencies as GPS.

“We remain gravely concerned that the Ligado Order fails to adequately protect adjacent band operations — including those related to GPS and satellite communications — from harmful interference impacting countless military and commercial activities,” the senators wrote.

Republicans Michael Rounds of South Dakota and Dan Sullivan of Alaska joined Democrats Tammy Duckworth of Illinois, Mazie Hirono of Hawaii and Mark Kelly and Kyrsten Sinema of Arizona in signing the letter.

Ligado Networks did not reply to Defense News’ request for comment.

More than a dozen federal agencies and departments urged the FCC not to approve the Ligado order prior to its 2020 decision.

The National Telecommunications and Information Administration led a coalition of federal agencies and departments urging the FCC to stay the order, citing the same concerns on the potential impact to GPS networks. The Defense Department and Transportation Department were among those who joined the National Telecommunications and Information Administration’s petition.

But the FCC voted 3-2 last year to deny the petition, allowing Ligado Networks to proceed with establishing its terrestrial wireless network as planned.

Several companies, especially in the defense and transportation industries, have also urged the FCC to reverse its decision. Notably, Lockheed Martin has joined the calls to keep Ligado Networks from establishing its 5G network in the L-band frequency 1-2 GHz range used by GPS.

The Defense Department and private sector arguments have found a sympathetic ear in Congress.

“We urge you to set aside the Ligado Order and give proper consideration to the widely held concerns across the executive branch, within Congress and from the private sector regarding the expected impact of the Ligado Order on national security and other systems,” the senators wrote.

Bryant Harris is the Congress reporter for Defense News. He has covered U.S. foreign policy, national security, international affairs and politics in Washington since 2014. He has also written for Foreign Policy, Al-Monitor, Al Jazeera English and IPS News.

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