LightSquared’s LTE network disrupts 75% of GPS devices in tests

Mobile broadband startup LightSquared’s GPS interference troubles aren’t over yet. The company’s LTE network has been found to disrupt 75 percent of GPS devices in a government test, Bloomberg reports.

The test, conducted by the National Space-Based Positioning, Navigation, and Timing (PNT) Systems Engineering Forum, found that 69 of 92 selected GPS devices “experienced harmful interference” within 100 meters of a LightSquared base station.

“LightSquared signals caused harmful interference to majority of GPS receivers tested,” according to a draft of the test report. “No additional testing is required to confirm harmful interference exists.”

For months, LightSquared has been facing criticism from the GPS industry and government agencies over the spectrum used by its LTE network, which is dangerously close to the wireless spectrum used by GPS devices. LightSquared has said that it’s working on reallocating the spectrum its network uses, but it also blamed the GPS industry for creating devices that don’t stay within their required spectrum ranges.

Most recently, LightSquared has said that a new antenna could help to alleviate GPS interference. It’s unclear if that new antenna was being used for this test. The company is also planning to run its base stations at lower power levels than the government test, which should interfere with fewer GPS devices, executive vice president Martin Harriman told Bloomberg.

Reston, Virginia-based LightSquared was founded by billionaire Philip Falcone with the goal of reselling its LTE mobile broadband network, which will cover up to 260 million people, to others. That’s not going to happen until the company can fix its GPS problems.

In an e-mail to Bloomberg, Harriman said LightSquared is “outraged by the illegal leak of incomplete government data… This breach attempts to draw an inaccurate conclusion to negatively influence the future of LightSquared and narrowly serve the business interests of the GPS industry.”