The Global Positioning Satellite System (GPS).
The primary purpose of the upgrade is to add an additional civilian signal and two additional military signals to be transmitted by each modified satellite. The satellites will also feature additional signal power and the ability to reprogram signals and power while in orbit, measures that improve the accuracy of the signals and also serve as a countermeasure to jamming attempts.
The contract will allow the Air Force to speed up its plans to modernize the constellation of 24 GPS satellites. The Air Force originally planned to wait until after all the Block 2R satellites were launched before moving forward with modernization plans using a new series of spacecraft, the Block 2F.
"Our team offered the Air Force a plan that will accelerate the
GPS modernization program by approximately eight years," said Dave Podlesney, GPS Block 2R project manager at Lockheed Martin Space Systems. "This modernization program will benefit all users of the GPS system."
Four of the 20 Block 2R satellites have already been launched,
including one in July on a Delta 2 from Cape Canaveral, Florida. The other 16 are scheduled for launch over the next several years. The fifth Block 2R satellite is tentatively scheduled for launch in November.
The decision also comes four months after the federal government decided to turn off "selective availability" on GPS satellites, a feature that intentionally degraded the quality of the GPS signals to civilian users to prevent them from being used to locate and target American or allied forces.
At that time, government officials said they also planned to add a second civilian signal to the GPS system in 2003 and then a third two years later -- a decision that may have led to the upgrade of the remaining Block 2R satellites, rather than wait until the Block 2F versions are launched later this decade.
A provision of the
fiscal year 2001 budget, signed into law by President Clinton in August, allows the Defense Department to spend GPS funds on modernization that supports civilian uses of the system.
The Air Force plans to move ahead with the advanced Block 2F model, building up to 33 satellites.
Boeing has contracts to build six of the satellites, with options to build six more. Boeing originally planned to build all 33, but the Air Force decided earlier this year to put the rest out to bid again because of advances in technology since the original contract award.
The Air Force is also beginning design studies of a new generation of GPS satellites. The new satellites, designated GPS 3, would not be ready for launch until later this decade.
advertisement
