Two contracts signed on 27 October will begin the development of new ground stations for Galileo, Europe’s satellite-navigation system. The work will cover stations that collect satellite-signal data and stations that send navigation messages back to satellites in orbit, forming part of preparations for Galileo’s second generation.
Indra Space will develop the stations under agreements involving the European Space Agency, the European Commission and the EU Agency for the Space Programme. The announcement concerns development and later qualification of the equipment, rather than the immediate opening of a completed network. Further units are intended to be produced and deployed progressively at Galileo sites around the world after the new designs have been qualified.
How the ground network supports navigation
Satellite navigation does not rely on spacecraft alone. The satellites transmit signals, but a ground network is needed to monitor their performance, calculate the information that users need and keep the service operating. For Galileo, ground sensor stations receive and collect data from signals broadcast by the constellation. That information is used at control centres to produce navigation messages.
Ground uplink stations then send those messages to the satellites, allowing the spacecraft to distribute the information through their own signals. The system is designed to provide positioning and timing information, functions used across areas including transport, maritime activity, rail, financial timing and rescue operations.
The planned sensor and uplink stations are intended to work with both the current Galileo satellites and the next generation now being developed. That is significant because the ground infrastructure must support a mixed fleet while newer spacecraft enter service over time. The contracts therefore deal with the network on Earth that sits behind the signals received by phones, vehicles and other compatible equipment.
New equipment and resilience measures
The ground sensor stations are planned to use a more modern ground-data-centre architecture and software-defined radio technology. Software-defined radio uses software for functions that were previously carried out mainly by fixed hardware, allowing a system to be altered or upgraded without replacing every part of the radio equipment. The intended aim is to make the stations easier to maintain and to introduce new features more quickly.
The sensor stations will also incorporate controlled reception pattern antennas. These are designed to help a receiver manage unwanted radio interference. The technology is intended to strengthen resilience against jamming, which can block or disrupt a signal, and spoofing, in which a receiver is presented with a misleading signal.
For the uplink element, the programme will develop phased-array antenna technology alongside conventional dish antennas. A phased array uses electronics to direct radio waves rather than relying solely on the physical movement of a dish. The planned approach is intended to improve communication with satellites and the availability of the uplink network. Its operational results will depend on the later qualification, production and deployment stages.
A step in a longer programme
Galileo entered Open Service in 2016 and already supports users around the world. Its next generation is expected to introduce enhanced services in the coming years, but the new ground stations announced this week are not yet operating stations. The current decision establishes the development work required to connect future spacecraft and services with the ground network that supports them.
The European Commission manages and funds the programme under the EU Space Programme. The European Space Agency leads the design, development and qualification of the space and ground systems, while the EU Agency for the Space Programme has responsibility for bringing satellites into service and overseeing operations. The division of responsibilities reflects the fact that navigation services depend on satellites, control systems and users’ equipment working together.
The new contracts mark a defined technical stage rather than the completion of an upgrade. Their immediate effect is to begin the design and development of sensor and uplink stations for the second-generation system. The practical measure of progress will come later, as equipment is qualified and additional stations are deployed across the worldwide network.
