What is OCX?
The Next Generation Operational Control System (OCX) is the future version of the Operational Control Segment (OCS) that commands and controls the GPS constellation. The ground system upgrade is needed to enable the full military and civil capabilities of the modernized GPS satellites. OCX will also enhance cyber security, information assurance, and overall GPS performance. OCX consists of three blocks, with Block 0 providing GPS III launch checkout capabilities and Blocks 1 and 2 adding incremental satellite command and control functions.