Tests show that even the modified plans of the company LightSquared to start up a national high-speed wireless broadband network would cause harmful interference with GPS signals, federal officials said in a letter released Friday.
"There appear to be no practical solutions or mitigations that would permit the LightSquared broadband service, as proposed, to operate in the next few years months or years without significant interference with GPS," officials said in a letter to the Commerce Department. They recommended no further testing.
The letter was signed by Deputy Defense Secretary Ashton Carter and Deputy Transportation Secretary John Porcari, and released by the Federal Aviation Administration.
The conclusion was based on an analysis of testing by a panel of experts on behalf of nine government departments and agencies.
Their determination that LightSquared's plan can't be saved without dangerous interference with GPS could be a severe blow to the company's hopes to begin commercial service.
LightSquared accused the panel of bias and urged the Federal Communications Commission, which has jurisdiction over use of the
electromagnetic spectrum, to retake control of the testing.
The expert panel has "deep ties with the same GPS manufacturers who have sold poorly designed equipment to America's farmers, public safety officials, military and government agencies," the company said in a statement. The statement said the panel didn't adequately investigate the impact of filtering technology on potential interference with precision GOP devices.
"The devices selected as part of the most recent round of testing include numerous obsolete and off-market GPS receivers that nearly guaranteed failure," the statement said.
LightSquared, which is based in Reston, Va., filed a complaint with the NASA inspector general earlier this week about the panel, the statement said.
The company has rights to use a section of the electromagnetic spectrum that abuts the portion used for GPS. Its broadband network
would employ thousands of ground stations to receive satellite signals. The company has pitched the network as a wholesale alternative to existing broadband networks that could bring high-speed wireless to people left out today and lower the price.
The possibility of widespread GPS interference only became well-known to the GPS community -- including first responders, agriculture, the military and aviation -- about a year ago.
A coalition of business and other interests opposed to LightSquared's proposal welcomed the government agencies' conclusion.
"LightSquared has been afforded every possible opportunity to make its technical case and has failed to demonstrate that it can avoid interference to many critical GPS-based activities," said Dale Leibach, a spokesman for The Coalition to Save Our GPS.