Preliminary test results released earlier this week confirm that the new broadband network proposed by LightSquared will cause interference with GPS signals if it is allowed to launch in the planned spectrum.

“The test data discussed today makes clear that there is substantial interference to GPS if LightSquared turns on high-powered terrestrial facilities in the spectrum next door to GPS,” said James Kirkland, Trimble vice president and general counsel and founding member of the Coalition to Save Our GPS, speaking at an event sponsored by the National Space-Based PNT Advisory Board. “The data confirm what the industry told the FCC before it granted the waiver and also confirms that there is no viable technical fix. It’s time for the FCC to stop squandering resources trying to find a solution to an unfixable problem. Instead, it should focus its efforts on finding spectrum that LightSquared can operate in–where LightSquared won’t interfere with GPS.

“When it comes to broadband and GPS, it’s not an either/or situation – the United States can, and should have both. LightSquared says it has other spectrum and it should use it,” Kirkland said.

A waiver granted to LightSquared in January by the FCC’s International Bureau allows the dramatic expansion of terrestrial use of the mobile satellite spectrum (MSS) immediately neighboring that of the GPS using extremely high-powered ground-based transmissions. Tests have shown that these transmissions will cause interference to hundreds of millions of GPS receivers across the United States.

At the event, Kirkland and government representatives discussed testing conducted to measure interference to GPS receivers used in aviation and other critical government applications. In at least one test, LightSquared failed to deliver test equipment that matches its proposed operations, thus causing optimistic results – and even those optimistic results showed interference.

“It’s clearly a good thing that LightSquared is trying to do,” Kirkland said. “No one in the GPS industry opposes its goals of increasing wireless data capacity and competition, but the available data has shown overwhelming interference, and LightSquared should not be allowed to launch in the spectrum adjacent to GPS.”

A joint industry report is due to the FCC on June 15th, when the FCC will begin a public comment period before making its final decision.

For more information, visit the Coalition to Save Our GPS website.


Learn More About This Issue at the Survey Summit! At the ACSM Annual Conference being co-hosted by Esri in San Diego July 9-12, Peter Large, vice president of Trimble, and the Coalition to Save Our GPS, along with Jeff Carlisle, executive vice president of Regulatory Affairs at LightSquared, will deliver each perspective on this issue and be available for questions. Along with their presentations, there will also be a special forum with industry leaders from the National Society of Professional Surveyors (NSPS), American Congress on Survey and Mapping (ACSM), GPS World, GPS manufactures, Coalition to Save GPS, and LightSquared. You'll be able to hear first-hand the details of the threat to GPS and learn what you can do about it. POB contributing editor Joseph V.R. Paiva will moderate the special forum. Register to attend at www.surveysummit.com.