The member nations of the International
Telecommunications Union (ITU) have decided not to even consider proposals at this month's World Radio Conference (WRC) in Istanbul to require spectrum sharing in the frequency band currently used by the Global Positioning System (GPS). Industry consultants said the development will ensure the safety of GPS-based aircraft navigation systems.
Some ITU members had backed a WRC-2000 proposal that would have required sharing of the GPS frequency band with mobile satellite systems, which would provide global cellular-type mobile phone service via satellite. That position was strongly opposed by the U.S., which has spent more than $14 billion to develop GPS since the early 1980s, and by the International Civil Aeronautics Organization.
The U.S. argued, in widely circulated position papers prepared by Mitre Corp., a Pentagon-financed think-tank, that signal sharing between GPS and mobile satellite systems would cause a degradation in GPS performance. Mobile satellite operators, including the International Maritime Satellite Organization, as well as companies in Indonesia and the Middle East that are hungry for spectrum, argued that sharing is feasible.
The ITU Assembly agreed with the U.S. position, deleting the resolution calling for such sharing last week, the first week of the monthlong WRC-2000 conference. An ITU spokesman said the assembly deleted the GPS frequency-sharing resolution because technical studies conducted over the past three years demonstrated that "the conclusions that sharing is not possible are undisputed."
Richard Langley, a GPS consultant at the University of New Brunswick in Fredericton, called the move "good news" for GPS users, particularly aviation users. Airlines routinely use GPS guidance systems on trans-Atlantic flights, and the Federal Aviation Administration is developing an enhanced GPS system that will provide pinpoint accuracy, allowing it to be used for landings in weather that prevents visual approaches.
Langley said the ITU still hasn't resolved another GPS issue on its agenda: allocation of new frequencies for both the U.S. system and the new European-backed Galileo satellite navigation system.
Officials at the Department of Defense, which built and manages GPS, didn't return calls for comment by deadline.