U.S. gears up for defense of GPS spectrum

ALEXANDRIA, Va.—- Key federal spectrum officials voiced concern today that the United States might not gain the protection it needs for Global Positioning System satellite signals when an international meeting of radio spectrum users convenes in 1999.

At the World Radiocommunications Conference (WRC) in December 1997, the United States had what these officials describe as a "near miss" encroachment on GPS signals by mobile satellite system companies.

MSS operators want to use frequencies adjacent to the band allocated to GPS civilian users, but federal agencies believe that allocation may interfere with the GPS signals.

Officials speaking at the Civil GPS Service Interface Committee meeting hosted by the Transportation Department and the Coast Guard said MSS companies plan to make their case again at the next meeting in late 1999.

Dave Anderson, of the National Telecommunications and Information Administration, said, "Not many countries supported us in 1997, and I would not be surprised if...many countries will be converted by 1999." Anderson added, "If the MSS folks get their foot in the [frequency] door, it will go downhill from there."

Sally Frodge, of the Office of the Secretary of Transportation, explained the frequency battle simply: "There is only so much spectrum to go around."

Jerry Markey, head of the spectrum office at the Federal Aviation Administration, said the debate at WRC '99 will come down to a question of "safety-of-life" vs. commercial systems.

He said the dispute between GPS and MSS could be eliminated if commercial operators built handsets that included filters to eliminate interference. But, Markey added, this would mean hand-held receivers "might cost $250 each [instead of] $100.... Multiply that difference by 1 million users, and you understand it's all about money."

Markey gave the United States a "50-50 chance" of protecting the GPS spectrum at WRC '99. "We didn't escape at WRC '97," Markey said. "We were wounded because they managed to get on the agenda for 1999."

Keith McPherson, augmentation manager for the Global Navigation Satellite System program office at Airservices Australia, urged the United States to organize its spectrum defense for WRC '99 earlier and better than it did for WRC '97. McPherson said that during that meeting, "Your Secretary of Defense [William Cohen] was calling defense ministers around the world for help."