AF gen: GPS, LightSquared ‘can’t coexist’

The Air Force's space boss said his top priority is protecting GPS, and a proposed broadband network threatens it.

The boss of Air Force Space Command, Gen. William Shelton, does not want to get any more mixed up in the political imbroglio between the FCC, Republicans, Democrats and the broadband startup LightSquared. His job, he told reporters Tuesday, is to protect the Global Positioning System, and to that end, he reaffirmed at the Air Force Association’s trade show that GPS and LightSquared’s proposed network “cannot coexist.”

Simple as that.

He said as much during a question and answer session after a speech to the convention and then again to reporters in a press briefing afterwards. In fact, Shelton even picked up a pen and drew a diagram to illustrate how LightSquared’s network effectively jams the signal that military GPS receivers need to get their precise timing and location data. Shelton pointed to his diagram and said that even under LightSquared’s alternate proposal for its network, which would move its signal farther away from GPS, it would still squelch the harmonic frequencies that precise receivers use.

As for the “filters” LightSquared wants to develop to protect GPS receivers, Shelton repeated that it could cost billions of dollars and take a decade to install them on all of the military’s GPS units — if they work. That’s not gonna happen. The only answer, he concluded, is “spectrum reassignment” — the FCC would have to move LightSquared up or down the spectrum. The problem there, of course, is that other users are already occupying those parts of the band, but that’s the FCC’s problem, not the military’s.

So did the White House pressure him to change the testimony he planned to give about this to the House Armed Services Committee?

“Any time, in the past and in the future, that I’m called to testify I’ll do my best to present the facts as I know them,” Shelton said. “The real issue here, certainly, from my perspective, is protecting the GPS service.”