Overview
The global positioning system IIF (GPS IIF) is an upgrade of the original GPS, which is a worldwide timing and navigation system that utilizes 24 satellites positioned in orbit approximately 12,000 miles above the Earth's surface. These satellites continuously transmit digital radio signals pertaining to the exact time (using atomic clocks) and exact location of the satellites. By referring to signals transmitted by four satellites, the GPS can be used to calculate longitude, latitude, and altitude. The Department of Defense originally developed the GPS for all-weather military applications, but the system is available at no additional charge for civilians and commerce.
New Capabilities
As a result of increased civil and commercial use as well as experience in military operations, the U.S. Air Force is introducing the following new capabilities and technologies to the GPS IIF to sustain the space and control segments while improving mission performance:
- Twice as many navigation signals, including three new signals dedicated to civilian and commercial use, including support for codeless receivers
- UHF crosslink commanding and telemetry for improved user accuracy
- An update of the navigation payload architecture
- Operational capability for a new military signal
Long-Term Growth Capability
The original GPS IIF design incorporates flexibility to accommodate new and evolving requirements and upgrades. This flexibility includes the following areas:
- Processor throughput
- Memory margins
- Weight
- Power
- Thermal requirements
- Internal volume
GPS Satellite Experience
After more than 30 years of teamwork with the U.S. Air Force, Boeing has produced 40 Block I, II, and IIA GPS satellites. Boeing is currently building the Block IIF.
For more information, read the GPS IIF/III (PDF) overview.
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