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[infowar.de] WSJ 26.03.03: U.S. Bombs GPS-Jamming Sites In Iraq, Possibly Sold By Russia
Wall Street Journal
March 26, 2003
U.S. Bombs GPS-Jamming Sites In Iraq, Possibly Sold By Russia
By Anne Marie Squeo, Staff Reporter Of The Wall Street Journal
Just days after the Bush administration accused Russia of selling equipment
to Iraq that could interfere with satellite-guidance systems, U.S. military
officials said they bombed six sites containing such devices.
Military officials have been concerned that Saddam Hussein's government
would employ jammers against the U.S. Global Positioning System. The U.S.
increasingly relies on the system for guiding weapons, tracking its forces
and enabling individual pilots and soldiers to know exactly where they are.
Inexpensive jammers, including hand-held devices, can be bought on the
Internet, though Iraqi forces apparently were using bigger,
"We have noticed some attempts by the Iraqis to use a GPS-jamming system
that they have procured from another nation," said Maj. Gen. Gene Renuart,
the director of operations at U.S. Central Command in Qatar. He didn't
mention Russia, which has denied U.S. allegations that it sold such
equipment -- as well as antitank missiles and night-vision goggles -- to
Air strikes by allied pilots in recent days destroyed six jammers the U.S.
was able to identify, Maj. Gen. Renuart said, adding that one of the sites
was hit by a GPS-guided bomb. Gen. Richard Meyers, chairman of the U.S.
Joint Chiefs of Staff, said he believes those were the only jammers
deployed by the Iraqis.
While U.S. officials stressed that the jammers didn't affect GPS-reliant
weapons or equipment, the timing of the U.S. complaint to Russia and the
bombing raids suggest that they have caused problems, some military
analysts said. "If the jamming equipment was powerful enough to locate and
target, it probably had some effect on U.S. bombs," said Anthony Cordesman,
a military analyst at the Center for Strategic and International Studies, a
Washington think tank.
U.S. officials say the majority of their bombs and missiles have hit their
targets, but some clearly have gone astray -- missiles have landed in both
Iran and Turkey. Military officials declined to provide specifics about
where the Iraqis had placed the jamming devices.
GPS satellites, conceived by the military during the 1970s, circle the
globe twice a day, continuously beaming radio signals that provide timing
and logistical information to anyone with a GPS receiver. But because the
signal travels 11,000 miles to get to the Earth's surface, it is fairly
weak, and thus can be easily interfered with, Air Force officials and GPS
The current constellation of about 24 satellites emits two signals -- one
dedicated to the military and another that has been made available to
commercial users around the globe such as telecommunications and
transportation companies. The military signal is configured so it is
difficult to interrupt, but the commercial signal is used to "find" the
To jam GPS-reliant equipment, a transmitter either would attempt to emit
"interference" on the same frequency the GPS operates or use additional
power to knock out a broader spectrum of frequency, GPS specialists say.
This interference would target receivers of such signals, not the
Military officials have refused to say if the GPS has been jammed in
battle. But fixes have been developed to overcome the problem. For
starters, the Air Force and Navy both have electronic-warfare aircraft that
were altered in the 1990s to detect GPS jams, said James Hasik, co-author
of "The Precision Revolution: GPS and the Future of Aerial Warfare."
Military officials also upgraded Raytheon Co.'s Harm missile so it can home
in on GPS-jamming emissions, Mr. Hasik added.
Also, the military has alternative systems that can minimize the effect
GPS-jamming can have on a bomb. Joint Direct Attack Munitions, which pair a
GPS-guidance kit with a gravity bomb, also have a separate
inertial-navigation system that is used as a primary means for finding
targets, says a spokesman for Boeing Co., which makes the JDAM. This allows
the bomb to find its target even if it loses its GPS signal. Analysts
suggest that could be one reason a GPS-aided weapon could make a direct hit
on one of the Iraqi jammers, as U.S. military officials said.
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