GAlileO 2Nd GeNeRATiON WHAT ' S NeW AbOuT THe cONSTell ATiON

by Fulvia Croci

Galileo, Europe's satellite navigation constellation, is to reach higher levels of accuracy thanks to its second-generation (G2) satellites. Last July, the European Space Agency issued 11 open invitations to tender totaling EUR 950 million, not yet formally awarded, with a view to equipping the satellites with new functions in the present decade.

G2 satellites boast numerous technological upgrades, developed through the EU and the ESA R&D programs. Galileo is Europe’s civil global satellite navigation constellation offering meter-scale accuracy to more than 2 billion users worldwide. With improved accuracy, the new generation should be able to offer decimeter-scale precision positioning to all. These Galileo second generation (G2) satellites will revolutionize the Galileo fleet, joining the 24 Full Operational Capability (FOC) satellites currently in orbit plus the ‘Batch 3’ satellites now being tested. The 11 procurements cover key areas of the G2 ground segment, including ground control, i.e. the key infrastructure for the operation of the system that will be used to monitor and integrate the services of all satellites.

Moreover, the above contracts include also the 'System Engineering and Technical Assistance (SETA) in

Here are the areas of interest in detail: eSA has financed 11 new procurements with a view to equipping G2 satellites with new functions for different users ESA's ESTEC center in Noordwijk, the Netherlands, is the test center of the Galileo constellation.

Credits: Sjm Photography

• G2 Ground Control Segment (G2GS) used to ensure full control of the G2 satellites.

• G2 In Orbit Validation Ground Mission Segment and Secured Facility used to ensure the provision of new and legacy capabilities to Galileo users.

• G2 In Orbit Validation Security Monitoring (G2 Sec Mon) to monitor the security of all elements of the Galileo system.

• G2 System Test Bed (G2Stb) for monitoring of the Galileo constellation and the development and validation of all new G2 capabilities, excluding the secure high-accuracy PRS service (Public Ragulated Service).

• G2 Public Regulated Test Bed (G2PRSTB) – for the monitoring of the Galileo PRS and the development and validation of all new G2 PRS capabilities.

• G2 Security Chain Test Bed (G2SC) – to ensure full compatibility between the security elements of the G2 system: space, ground, receivers.

• G2 Filling Device (GS FD) – cryptographic element to enable the secure communication and initialization between the different security elements of the G2 system.

Phase CDE', which entails the recruitment of European experts to provide assistance to the ESA.

The new G2 satellite constellation will be constructed in a short time scale, with their first launch expected halfway through this decade, allowing the system to commence operations as soon as possible. Electric propulsion and an enhanced navigation antenna will be among the technological innovations of the constellation; their fully digital payloads are being designed to be easily reconfigured in orbit, enabling them to actively respond to the evolving needs of users with novel signals and services. In addition, all satellites will be equipped with advanced jamming and spoofing protection mechanisms to safeguard Galileo signals. Galileo second-generation (G2) satellites will make it possible for users to acquire the signal faster on their smartphones and access services when switching on their devices, with less energy consumption.

As a further feature, the constellation will also provide an advanced search and rescue (SAR) function to initiate rescue operations. The new systems will ensure more effective communication with populations affected by natural disasters. Satellites will be able to deliver distress signals independently of telecommunication service providers, using the Galileo navigation signals as a one-way messaging service.

"These procurements," said Javier Benedicto, ESA Director of Navigation, "represent an important step forward for Europe, through the implementation of innovative technologies to ensure an order of magnitude improvements in precision. G2 is a unique program for Europe, an ambitious evolution of the Galileo system, encompassing both legacy services and the future of navigation, positioning, and timing capabilities for all users to come."