WASHINGTON (AP) _ The Pentagon wants to turn up the power on its network of satellites used to guide U.S. troops and the bombs they fire.
The $200 million proposal is one of the military's first to fulfill Defense Secretary Donald H. Rumsfeld's plans to protect the United States from a ``space Pearl Harbor.''
The money would pay to upgrade the newest Global Positioning System satellites, which have yet to be launched. That would allow the transmission to military receivers of signals that are eight times more powerful those sent by the current generation of satellites.
These boosted signals would be powerful enough to burn through electronic jamming put up by an adversary. American troops would not get lost and satellite-guided smart bombs would still find their targets.
The ever-more-popular GPS devices used by civilians would not be affected or receive the boosted signal, defense officials said.
By 2006, enough new satellites would be in orbit so that troops with GPS receivers should be able to receive a boosted signal anywhere on the Earth's surface, according to the plan.
The Bush administration is seeking about $50 million for the program in its proposed 2003 budget.
A GPS receiver works by comparing the radio signals it receives from several satellites. Each signal can be computed to learn the receiver's distance from each satellite. The distances can be compared, and, like a surveyor triangulating his location, the receiver can figure out where it is.
The military uses the system for navigation and targeting. During the Gulf War, U.S. tanks relied on GPS directions to find their way around the desert in Iraq and Saudi Arabia.
But the increased power would only be transmitted on channels used exclusively by the military. Over-the-counter GPS locators used by foreign militaries, merchant ships and expensive cars would continue to receive the low-power transmissions, leaving them more vulnerable to jamming.
Just one boosted signal would make it easier for receivers to find other, low-power satellites, even in an environment full of electronic noise thrown up to drown out the GPS signal, military officials said.
The plan would allow the U.S. military to jam an adversary's over-the-counter GPS equipment on a battlefield, but still use its own.
Jamming GPS signals is relatively easy, according to a Transportation Department report last year on threats to the system. But it is unclear if anyone, except perhaps the United States, has used this technology on the battlefield.
``Short, lightweight, short-lived jammers with power from one to 100 watts could cost less than $1,000,'' the report says. ``These jammers can be built by people with basic technical competence from readily available commercial components and publicly available information.''
Some experts, who note the U.S. commerical sector has become reliant on GPS for everything from navigation to setting clocks used to time financial transactions, suggest the boosted signals also be made available to civilians.
``I won't be critical of them taking steps to protect (Defense Department) infrastructure first,'' said L. Paul Bremer III, a former U.S. ambassador-at-large for counterterrorism who has studied the issue. ``But protecting GPS needs to be looked at much more broadly.''
Boosting the military GPS signal is part of Rumsfeld's push to protect the U.S. advantages that arise from its supremacy in space, said Air Force Col. Roger Robb, a GPS program official, in a written response to questions.
Until shortly after he was nominated by President Bush in January 2001, Rumsfeld was chairman of the Commission to Assess United States National Security Space Management and Organization.
The commission created by Congress concluded that the government was becoming more reliant on space for its military and intelligence programs, but was doing little to protect these advantages against attack.
The commission said a lack of attention by the government to its satellites and space policy makes the United States ``an attractive candidate for a space Pearl Harbor.''
Since becoming defense secretary, Rumsfeld has also reorganized some of the senior command structure for military space programs.
For example, a new generation of communications satellites would be able to transmit through the electromagnetic pulse created by a nuclear detonation, according to officials at the Space and Missile Systems Center at Los Angeles Air Force Base, Calif.
The administration is seeking $825.8 million for the program in 2003. The launch of the first of five of these satellites is expected in 2005.