LightSquared booth at Satellite 2011 Convention at Washington Convention Center in Washington, March 15. (Jeffrey MacMillan/FOR WASHINGTON POST)

The FCC, which has been criticized for its handling of LightSquared’s waiver to conditionally launch a terrestrial network, said in a public notice Tuesday that a proposed solution to interference problems needs more testing.

Specifically, LightSquared said last June it would move its terrestrial transmitters — which were granted through the FCC waiver — to a lower part of the satellite spectrum it shares with GPS receivers.

That helped with some interference problems, but not for high precision GPS receivers, including devices used for national security and aviation applications, the FCC said.

“Additional testing is therefore necessary,” the FCC said in its notice.

FCC chairman Julius Genachowski will testify Thursday before the House Armed Service Committee hearing on GPS and national security.

The agency has defended a controversial waiver it granted last January that allows LightSquared to operate smartphones and other devices on its 4G LTE network. The FCC said the waiver is conditional and won’t allow the company to light up the network until GPS interference issues are resolved.

But some lawmakers and GPS operators said the agency appeared to fast-track the company’s ability to get its network off the ground, without fully testing interference potential.

The National Telecommunications & Information Administration last Friday sent a letter to senior officials at the Department of Defense and Federal Aviation Administration, asking for the agencies to coordinate with LightSquared on further testing of technology for interference with GPS. NTIA head Lawrence Strickling asked for the tests to be complete by Nov. 30 and said a second round of tests would be necessary after that.


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