The US Pentagon has cancelled a ground control system for the US military's GPS satellite navigation network, the Global Positioning System Next-Generation Operational Control System (OCX), due to persistent issues. The OCX program was officially terminated by Michael Duffey, the Pentagon’s defense acquisition executive, on April 17. The decision ends a 16-year effort to design, test, and deliver a command and control system to the military's constellation of GPS navigation satellites. The system was designed to handle new signals from the latest generation of GPS satellites, GPS III, and modifications to ground monitoring stations around the world. The cost of the program, which was awarded to Raytheon, now known as RTX Corporation, grew to nearly $8 billion, nearly as much as the cost of an entire fleet of new GPS satellites.