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Space
Programs Inching Toward Stronger
GPS Signals by 2010
5/1/2006
By
Tom Sawyer

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| Swarming.
Connecting NAVSTAR (bottom), GALILEO (top) and GLONASS is a
global effort(Illustration by Guy Lawrence for ENR) |
Owners, architects, consulting engineers and
contractors who use wireless devices to monitor, survey and build
expect to get greater precision from global positioning systems
in the next few years. But international cooperation will determine
just how fast it happens.
Major vendors of global positioning receivers
now claim to link with American and Russian satellites, offering
more accuracy and reliability than the U.S. NAVSTAR GPS system alone.
This is a much-needed step in our industry, says Tim
Tometich, GPS manager of McAninch Corp., an earthmoving contractor
in West Des Moines, Iowa.
Financial and political volatility has hampered
progress of the Global Navigation Satellite System (GNSS). But the
network is starting to show signs of life again. As more nations
launch wireless navigation systems, the all-encompassing term GNSS
is slowly overshadowing GPS, which refers to the U.S.
network alone.
Major positioning vendors, namely, Trimble
Navigation Ltd., Topcon Positioning Sytems Inc. and Leica Geosystems
Inc.released new GNSS receivers this year. Users say the costs
have not changed but GPS-only units are dropping in price by as
much as 20%.
Vendors promise links with the European Unions
forthcoming GALILEO satellite network, due in 2010 but two years
behind schedule. Meanwhile, the Russian Federation, which once neglected
to maintain its GLONASS networkresulting in a 50% drop in
working satellites since it went online in 1995plans to send
up several more birds by 2007.
The U.S. Dept. of Defense, which operates
GPS, also is upgrading. It launched a modernized bird
last September, with more expected to be flown in 2008. Our
dependence on these types of systems is only going to increase,
says Charles Dull, assistant director of geospatial applications
for the Dept. of Agriculture Forest Service.
With more receivers available with GNSS interoperability
this year, construction users have an increased availability
in positioning when working in difficult environments, such as around
trees, says Mark Nichols, general manager of Caterpillar Trimble
Control Technologies LLC, a joint-venture research and development
company in Dayton, Ohio. An expanded global network will boost signals
inside urban canyons as well, Dull adds.
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