LOS ANGELES (KNX 1070) — A planned nationwide 4G broadband service threatens to cause “widespread, severe GPS jamming,” according to a recent GPS industry study and reported by KNX Newsradio.

Millions of GPS units are now in our cars, boats, planes and even smartphones.

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A company called Lightsquared is hoping to begin testing the service this fall using 40,000 transmission towers.

Jeffrey Carlisle, an executive vice-president at Lighsquared claims the GPS study, done by GPS manufacturer Garmin, is faulty, because the correct filters were not used. But he concedes there may be some interference to GPS signals which, in his view, may require modification to some exiting GPS units.

Garmin’s Ted Gartner counters that his company has been unable to obtain the filters from Lightsquared, but doubts they would change the outcome of the study.

Garmin’s Ted Gartner Expresses Concern About Planned 4G Service

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The FAA and U.S. military have now expressed their concern.

KNX 1070’s Charles Feldman Reports

An FCC spokesman tells KNX that “we recognize there is a potential for interference; it’s a concern.”

The FCC has ordered new tests to be conducted and says Lightsquared will not be allowed to start its 4G service until all parties involved are satisfied.

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