Architecture Evolution Plan (AEP)

The Air Force currently commands and controls the operational GPS constellation through a system called AEP. The system is capable of managing all of today's GPS satellites.

AEP refers to the Architecture Evolution Plan implemented in 2007. Under this plan, the Air Force replaced its original, mainframe-based GPS master control station with an entirely new one built on modern IT technologies.

The AEP system improved the flexibility and responsiveness of GPS operations and paved the way forward for the next generation of GPS space and control capabilities.

Utilizing commercial off-the-shelf (COTS) products, AEP also improved GPS monitor stations and ground antennas, substantially enhancing sustainability and accuracy.

AEP features an alternate master control station — a fully operational backup for the master control station.

Upgrades

• Modernized Civil Navigation (CNAV): In 2014, AEP was upgraded to support CNAV capabilities, allowing GPS Block IIR-M and IIF satellites to broadcast pre-operational navigation messages on the L2C and L5 signals. Learn more
• In 2016, the AEP COTS hardware and software baselines were upgraded with improved cyber security and improved supportability, to support operations into the 2020s.
• GPS III Contingency Operations (COps): In 2019, AEP will be upgraded to command and control GPS III satellites with the COps program. Learn more
• M-Code Early Use (MCEU): In 2020, AEP will be upgraded to provide core capabilities of the modernized military GPS signal, known as M-Code, to the military GPS user community under the MCEU program. Learn more

Next Generation Operational Control System (OCX): In the future, AEP and the entire GPS control segment will be replaced by OCX. Lockheed Martin will be under contract to sustain the GPS ground control segment, including AEP, until OCX becomes operational. Learn about OCX

More Information

• Nov 2018: 2nd SOPS Reaches GPS Milestone with AEP 7.5 Command (AF.mil)
• Jan 2013: Lockheed Martin Awarded $100 Million Contract to Sustain Ground Station for Global Positioning System (lockheedmartin.com)
• Apr 2011: 50th Space Wing Officials Accept Ground System Upgrades (AF.mil)
• Sep 2007: 50th SW Completes Transition to New GPS Control System (AF.mil)

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