On Feb. 15, following a conclusion from the NTIA that there is no practical way to mitigate the potential interference from the LightSquared network, the FCC issued a public notice stating that it intends to rescind the company's conditional waiver and suspend indefinitely its ATC authorization.

This story was first published on Feb. 14 but has been updated to include the latest developments.

Ina letter to the FCC chairmanon Feb. 14, the National Telecommunications and Information Administration (NTIA) issued its conclusion on the proposed LightSquared deployment of terrestrial operations on GPS services.

“Based on NTIA’s independent evaluation of the testing and analysis performed over the last several months, we conclude that LightSquared’s proposed mobile broadband network will impact GPS services and that there is no practical way to mitigate the potential interference at this time,” the letter stated. “Furthermore, while GPS equipment developers may be able to mitigate these issues via new technology in the future, the time and money required for federal, commercial, and private sector users to replace technology in the field and the marketplace, on aircraft, and in integrated national security systems cannot support the scheduled deployment of terrestrial services proposed by LightSquared.”

The agency said there are no mitigation strategies that both solve the interference issue and provide LightSquared with an adequate commercial network deployment.

In response to the NTIA letter, FCC spokesperson Tammy Sun issued a statement indicating that the matter is nearing a resolution. As a result of NTIA's conclusion, the Commission will not lift the prohibition on LightSquared, the statement said. It added: "The International Bureau of the Commission is proposing to (1) vacate the Conditional Waiver Order, and (2) suspend indefinitely LightSquared’s Ancillary Terrestrial Component authority to an extent consistent with the NTIA letter."

The FCC issued a public noticeon Feb. 15 inviting comments in response to its conclusions. The deadline for comments is March 1, 2012.

The Coalition to Save Our GPS was quick to respond to the news. “Today’s release of the NTIA’s conclusions and the FAA and government interference findings represent a pivotal moment in the year-long testing of harmful interference to GPS that followed the FCC International Bureau’s January 2011 order granting LightSquared a conditional waiver,” said Jim Kirkland, vice president and general counsel of Trimble, a founding member of the Coalition to Save Our GPS. “The FCC has acted appropriately by declaring that its non-interference condition has not been satisfied and that LightSquared will not be permitted to move forward with its proposal to build a nationwide high-powered terrestrial network in the mobile satellite band.

“The Coalition stands ready to work with the NTIA and the FCC to address the important policy issues relating to longer term use of satellite spectrum and reduction of potential interference to maximize the efficient use of all satellite spectrum,” he said.

LightSquared, which noted that it “profoundly disagrees with both the NTIA’s and the PNT’s recommendations,” said it remains committed to finding a resolution with the federal government and the GPS industry to resolve concerns. Ablog postby Jeff Carlisle, LightSquared executive vice president for regulatory affairs and public policy, cited continued strong support from members of Congress and state elected officials from both parties around the country.