GPS Next Generation Operational Control Segment (OCX)


OCX is the command and control component of the next generation GPS. The GPS mission is to deliver sustained, reliable GPS capabilities to America’s warfighters, our allies and civil users. 



The current OCX contract was awarded in February 2010 to replace the current Operational Control System (OCS) functionality, while adding the following:

  • Modern flexible, adaptable, and modular architecture based on service-oriented architecture principles

  • Backward compatibility to control existing GPS satellite families

  • The ability to fly GPS III satellites, control modernized signals (M-Code, L1C, L2C, L5) and support present and future information assurance and cyber needs

  • System-wide information assurance hardening detects and protects against cyber-attacks

  • Improved mission assurance features that respond to attacks and enable rapid restoration to full mission capability



OCX will provide command, control and mission support for the GPS III and legacy satellites using an expandable robust information assurance architecture. OCX will provide higher accuracy, integrity and availability of the system through the combination of worldwide measurements of navigation signals, a finely tuned Kalman filter and a network to upload the commands and messages to the satellite constellation. OCX is critical to continuing high priority national efforts to modernize GPS with new military and civil positioning capabilities, including enhanced security, precision, reliability and integrity.


OCX will consist of the following elements:

  • Master Control Station and Alternate Master Control Station  

  • Dedicated Monitor Stations

  • Ground Antennas

  • GPS System Simulator 

  • Launch and Checkout System   


  • OCX will deliver full command, control and mission support capabilities

  • Control all Modernized Civil Signals (L1C, L2C and L5)

  • Control Modernized Military signals (M-Code)

  • Add capability to launch and operate GPS III space vehicles

  • Enable growth to future GPS architectures


  • OCX will provide significant Information Assurance improvements over the current GPS OCS

  • Prevent, detect attacks          

  • Isolate, contain and operate during cyber attacks


  • The Master Control Station and Alternate Master Control Station will incorporate constellation management functions for all phases of each vehicle, through Command and Control, Mission Planning, Navigation and Data Analysis and Dissemination


  • The remote ground assets – the monitoring stations and ground antennas - will support data links and signals between the control system and the space vehicles


  • The GPS Systems Simulator will serve as a development and sustainment test driver for the MCS software and remote ground assets; the Standardized Space Trainer is a dedicated training system used for operator training



PRIME CONTRACTOR:  Raytheon Information and Intelligence Systems (Aurora, CO)


(Current as of April 2018)