Pentagon Issues New GPS Performance Guides
- By Joab Jackson
- Oct 19, 2001
Paving the way for more accurate GPS readings for the public, the Department of Defense has released new performance standards for civilian use of its Global Positioning System, the department announced Oct. 19.
These specifications codify the department's announcement last year to discontinue its practice of degrading GPS accuracy for civil use.
Previously, GPS systems provided non-military users a horizontal positioning accuracy of 100 meters; the new standards provide an accuracy of 36 meters.
GPS is a space-based, radio navigation system that was designed for U.S. and allied military forces as a global navigation tool. It is also used extensively by federal agencies for mapping, surveying, international air traffic management and global climate change research. GPS receivers also are sold in the commercial sector as navigational tools.
The new standards were created in response to President Clinton's May 2000 directive that the Defense Department stop using a technique called selective availability, which diminishes the signal accuracy from the standard positioning service, the civilian delivery mechanism of GPS.
This follows a 1996 directive from the White House to sharpen the accuracy of the commercial-grade signals from 100 meters to 10 meters by 2005.
The department also announced it will notify the civil user community of performance disruptions to the system, and that it plans to add improvements that will correct for ionospheric distortion and make better continuity of service.
These new services will be deployed with satellite launches scheduled between 2003 and 2012, with full operational capability expected in 2014.
The new standard can be found on the Web in PDF format at www.navcen.uscg.gov/gps/geninfo/2001SPSPerformanceStandardFINAL.pdf.
Joab Jackson is the senior technology editor for Government Computer News.