|Under deployment||INITIAL OPERATIONAL CAPABILITY (IOC)
FULL OPERATIONAL CAPABILITY
INTEROPERABILITY is essential, as both GPS and GALILEO are to be transmitting in the same frequency range and using the same message format, current receivers with appropriate firmware updates have the hardware capability to use both constellations for improved accuracies.
The dates above are supported by the Constellation Deployment Plan (to be confirmed) describing when each pair of GALILEO satellites is ready from production and when can they be deployed by the Soyuz launcher, up until IOC (Initial Operational Capability).
Where Soyuz rockets are to be used to deploy the satellites, following the validation tests performed to date. The picture above shows one GALILEO satellite and the Soyuz launcher.