Unmanned Vehicle GPS Developers Express Concerns About LightSquared

By Carlton Purvis

WASHINGTON - For months the general aviation industry has expressed their concerns about LightSqaured broadband plans causing interference with their GPS navigation systems. Now, the unmanned vehicle industry has voiced concerns that precision GPS systems in UAVs could also be severely affected by LightSquared’s broadband initiative. At the AUVIS 2011 Symposium, stakeholders had the opportunity to weigh in on LightSquared’s controversial plans to launch a nationwide broadband network.

A panel made up of Melissa Rudinger, of the Aircraft Owners and Pilots Association (AOPA); Ken Alexander, navigational team leader at the Federal Aviation Administration; Ann Swanson, an attorney representing Garmin; and Geoff Stern, vice president of spectrum development at LightSquared discussed pros and cons of LightSqaured’s plans to deploy 35,000 base stations in an effort to provide complete 4G broadband coverage to the entire United States.

Initial tests of the system show it would interfere with GPS signals. Stern says LightSquared has always been willing to compromise on a solution to the problem. In recent months aviation groups have called for LightSquared to stop their plans completely, but in today’s panel, all sides seem committed to seeing an outcome that would benefit all parties.

However continued finger-pointing on all sides shows that compromise is still a long way off.

Less than a week ago, LightSquared filed a letter with the FCC saying GPS manufacturers were to blame for unwanted interference for making devices that accepted frequencies outside of their licensed spectrum.

“Had the GPS industry complied with DoD’s recommended filtering standards for GPS receivers, there would be no issue with LightSquared’s operations in the lower portion of its downlink band,” LightSquared executive vice president for Regulatory Affairs & Public Policy, Jeffrey Carlisle said in the letter.

But Michael Ritter, president and CEO of NovAtel, a GPS manufacturer out of Canada, says that’s not how things happened.

In a comment during the question and answer session, Ritter said LightSquared should “tell the truth” about why GPS manufacturers designed devices to pick up frequencies in that part of the spectrum, and accept responsibility for being part of the problem. LightSquared is no stranger to the GPS industry. In fact, it’s where they got their start, he said.

LightSquared originally started as a satellite communications company and is a leading developer and supplier of mobile satellite communications services. GPS companies actually use LightSquared satellites to provide their services. In addition to the area on the radio spectrum in question, the company also holds several others.

Ritter explained that when some companies began services with LightSquared, they were told their devices had to pick up bands in LightSquared’s other frequencies to be flexible for possible changes. In doing so, these companies deliberately developed their GPS systems to pick up the frequencies in the band being disputed right now.

"Signals that GPS receivers listen to in the MSS bands are the differential corrections that are used to make the GPS more accurate. These are provided by Omnistar and Starfire utilizing the Inmarsat and Lightsquared satellites. Both contracts state that the GPS receiver has to listen to that entire band," according to Ritter.

Stern says LightSquared never told any customers how they had to make their devices to use its service.


View Recent News (by day)


Beyond Print

SM Online

See all the latest links and resources that supplement the current issue of Security Management magazine.