News from the European Space Agency (ESA)
Europe’s Galileo satellite navigation system continues to evolve. For the first time, end-to-end testing of the Galileo system demonstrated signal acquisition of an improved version of the Public Regulated Service (PRS), the most secure and robust class of Galileo services.
The system test extended from the Galileo Security Monitoring Centre in Spain and the Galileo Control Centre in Germany to a Galileo satellite at ESA’s ESTEC technical heart in the Netherlands, which then broadcast in turn to a user receiver.
Galileo’s PRS is an encrypted navigation and timing service for governmental authorized users and sensitive applications intended to remain available even in scenarios where other Galileo services might be degraded or jammed.
An initial version of the PRS signal has been broadcast by the satellites up to now, but as of next year the signals will evolve into an enhanced version known as Full Operational Capability Public Regulated Service (FOC PRS), which has been defined in close collaboration with the European Commission, the European Union Agency for the Space Programme (EUSPA) and the EU Member States.
The system’s FOC PRS capability is being enabled by an expansion of the Galileo ground mission segment — important upgrades of the Galileo Security Monitoring Centres (GSMCs) in St. Germain-en-Laye, France, and Madrid, Spain. These two sites oversee PRS provision and monitor its performance.
This coming version of the security monitoring centers, set for the following year, is being developed by an industrial consortium led by Thales Alenia Space in France.
Meanwhile the progressive deployment of remote system infrastructure is taking place over the course of this year, readying Galileo sensor stations to receive the upgraded PRS signals.
“To qualify, the FOC PRS Signal in Space required a major Galileo end-to-end test, demonstrating the compatibility of the space segment with the ground and user segments, called the System Compatibility Test Campaign (SCTC),” explained Federico Di Marco, ESA SCTC test director. “This test involved all Galileo key players spread across Europe, requiring close cooperation between the teams and months of preparation.”
The SCTC was led by an ESA engineering team from the agency’s ESTEC technical center in Noordwijk, the Netherlands supported by the System Engineering Technical Assistance industrial team led by Thales Alenia Space in Italy and in close collaboration with the operations team supervised by EUSPA.
“The testing involved three centers across Europe: the GSMC in Madrid, the Galileo Control Centre in Oberpfaffenhofen, and ESTEC hosting an actual Galileo satellite plus FOC PRS user receivers,” added Edward Breeuwer, who is in charge of Galileo system qualification at ESA.
The FOC PRS signal was generated at the GSMC, sent to the German control center, then uplinked to the Galileo satellite at ESTEC, where the satellites are tested for space in advance of launch. The Galileo satellite then broadcast the FOC PRS signal in turn, to be picked up by a pair of receivers also on site: one developed by Antwerp Space under ESA contract and the other developed by Leonardo as part of a national development undertaken by Italy’s Competent PRS Authority, charged with overseeing the country’s PRS use.
“This marks the first time we have integrated such a nationally developed receiver within a system test activity,” said Fabio Covello, who oversees system security for ESA. “Having achieved this for PRS makes us very proud. We are confident that this experience can pave the way for future fruitful collaborations between the Galileo Programme and EU Member States, in the frame of specific tests to guarantee compatibility between the ESA-developed system and nationally developed PRS receivers.”
This successful outcome sets the scene for the PRS qualification at ground segment and system level, followed by operational validation planned in coming months, culminating in the first FOC PRS Signal In Space operational broadcast, in the course of next year.
