The GPS modernization program is an ongoing, multibillion-dollar effort to upgrade the features and overall performance of the Global Positioning System. The upgraded features include new civilian and military GPS signals.
Improving GPS performance through modernization promotes the U.S. policy of maintaining leadership in the service, provision, and use of global navigation satellite systems.
Learn More About a Specific Aspect of GPS Modernization
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Space SegmentThe GPS space segment consists of a constellation of satellites transmitting radio signals to users.
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Control SegmentThe GPS control segment consists of a global network of ground facilities that track the GPS satellites, monitor their transmissions, perform analyses, and send commands and data to the constellation.
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New Civil SignalsA major focus of the GPS modernization program is the addition of new navigation signals to the satellite constellation.
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Modernized Civil NavigationThe GPS modernization program is adding new civilian signals to the GPS constellation.
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GPS PolicySince the 1980s, multiple U.S. presidents have issued consistent policies encouraging the worldwide use of GPS for peaceful purposes. Congress has enacted elements of these policies as permanent law.
Schedule
GPS modernization involves a series of consecutive satellite acquisitions, including GPS Block IIR-M, GPS Block IIF, GPS III, and GPS III Follow-On. It also involves parallel improvements to the GPS control segment, including the GPS III Contingency Operations (COps), M-Code Early Use (MCEU), and Next Generation Operational Control System (OCX) programs.
We no longer provide current schedule information on this page. You can find recently released schedule information in our Public Presentations section.
We provide projected availability dates for the L2C, L5, and L1C signals on the New Civil Signals page.
Funding
GPS modernization involves the complete replacement of legacy GPS satellites and ground systems with newer, more capable ones. This effort requires significant resources from the Department of Defense, with contributions from the Department of Transportation. Full details are available in our Program Funding section.
Ending Selective Availability
The first step in GPS modernization took place in May 2000, when President Bill Clinton directed the Department of Defense to turn off the GPS Selective Availability (SA) feature.
SA was an intentional degradation of civilian GPS accuracy, implemented on a global basis through the GPS satellites. During the 1990s, civil GPS readings could be incorrect by as much as a football field (100 meters). On the day SA was deactivated, civil GPS accuracy improved tenfold, unleashing a worldwide revolution in civil and commercial applications.
In 2007, the government announced that GPS III will be built without the SA feature.