AMP AS SAYLIYAH, Qatar, Dec. 21 — The United States military has deployed a sophisticated ground-radar system here to help protect allied and American forces in the Persian Gulf region from Iraqi missile attacks, military officials say.
The radar — called the Joint Tactical Ground Station — is a mobile Army system that alerts commanders to hostile missile launchings, using data from space-based satellites. The information is also relayed instantaneously to missile defense systems, like the Patriot, that are deployed in the region, to help intercept incoming missiles.
These new radars are deployed overseas in only two other places — Germany and South Korea — and are a significant advance from the early-warning systems used during the 1991 Persian Gulf war. The single greatest loss of American lives in that conflict came when an Iraqi Scud missile hit a barracks in Dhahran, Saudi Arabia, killing 28 service members and wounding 98 others.
Iraq's military is smaller and less caable than it was a decade ago, American officials say, but its arsenal of Scuds, which could be tipped with chemical or biological weapons, still poses a major threat to American forces and allies in the region, like Israel.
Commanders here and at other American bases in the region said the ground-radar system, combined with other air defenses, gives them more time to warn troops of an enemy missile strike and to fire off a quicker and more accurate counterattack.
"It gives us early warning and it has huge coverage," said Lt. Col. Frank Molinari, commander of Army forces at this base, which is also home to a new command center that would serve as the military's headquarters for a war against Iraq.
The new radar, which was deployed here several months ago but only recently described in detail by officials here and in the United States, is one of several improvements the Pentagon has made since 1991 to detect and destroy Scud launchers and missiles, even after they have been fired.
The Patriot system fielded a decade ago was an antiaircraft defense that was modified to counter Iraqi Scud missiles, but experienced only mixed success. Unlike the older Patriot, which explodes near its target, the new Pac-3 model is designed to hit its target head-on. It is also more maneuverable and has better tracking and guidance systems.
Israel has also deployed an operational missile defense, called Arrow, and is ready to use it to protect Tel Aviv and other major cities if they come under fire from Iraq's Scud missiles.
In the gulf war, Iraqi forces used mobile launchers to fire Scuds and then fled into caves or culverts before allied warplanes could bomb them. The United States assigned nearly 2,500 missions to Scud-hunting but failed to score a confirmed kill against a mobile missile or launcher.
American commanders now plan to deploy Predator and Global Hawk surveillance aircraft, which can patrol continuously for 24 hours, as well as E-8C Joint Stars ground-surveillance planes, to detect mobile launcher movements and guide bombers to their targets faster with improved communications equipment.
American warplanes now carry more accurate laser-guided and satellite-guided bombs and missiles. Special Operations Forces will probably deploy to western Iraq in the opening hours of any war to destroy missile launchers that threaten Israel.
In an effort to learn more about how the Scuds operate, the Air Force last month launched a pair of the missiles — secretly bought from a former Warsaw Pact country — into the Pacific Ocean from Vandenberg Air Force Base in California. Sensors on the missile, as well as on nearby ships and planes, measured the missiles' trajectories.
In the gulf war, Iraq lobbed about 90 Scuds at Israel and allied troops in Saudi Arabia and other gulf countries. American intelligence officials believe that Iraq still has "several dozen" Scuds, including the Hussein version with a range of about 390 miles, and the Abbas version with a range of about 540 miles.
Iraq has also deployed short-range rockets, the Samoud and Ababil 100. American analysts say both of them exceed the 150-kilometer range limit — about 93 miles — that the United Nations imposed on Iraq's missiles after the gulf war.
American intelligence officials said they expect Iraqi commanders to deploy these short-range missiles to within range of American forces in Kuwait and possibly Turkey. "We are concerned about their being used in both the south and the north," one intelligence official said.
The United States Central Command has long sought to deploy the ground radar into the gulf region. The European Command, whose area of responsibility includes most of Europe, and parts of Africa and the Middle East, including Israel, has units stationed in Stuttgart, Germany, that can be sent anywhere in its region. The Pacific Command has units at Osan, South Korea.
When the Central Command failed to reach agreement to station the ground radar in Saudi Arabia, officials turned to Qatar, where some 3,000 American forces are stationed.
The radar system, made by Northrop Grumman, is a series of radars that pack into a large storage container and can be towed around by truck. It is small enough to fit on a C-141 transport plane, requires a small crew, and is relatively easy to set up and take down, officials said.
In the gulf war, space-based sensors that detected Iraqi missile launchings alerted officials at the North American Aerospace Defense Command in Colorado. Officials there telephoned commanders in the gulf to alert them to the threat, a former senior officer said.
"What Jtags does is allow a small portable piece of equipment to directly downlink data from satellites rather than having to rely on the cumbersome set of relays that we had to use in the gulf war," said the officer, Joseph G. Garrett 3rd, a retired Army major general who commanded all Patriot antimissile units in Saudi Arabia during the gulf war.
The ground radar's high-resolution displays give commanders the estimated launching point and time of a missile, its projected impact point and time, and its trajectory.
With the ground radar linked up with Patriot antimissile batteries, front-line commanders say the overall air defenses give them a greater sense of security against hostile strike.
"We have a good array of systems," said Col. Patrick Shaw, commander of the 386th Air Expeditionary Wing at Ali al Salem Air Base in Kuwait, just 39 miles south of the Iraqi border.