European time lords

Leading players in Europe’s timing community will synchronise the precision time signals underpinning the ambitious Galileo constellation of navigation satellites.

The Fidelity consortium was appointed by the Galileo Joint Undertaking in June and recently successfully passed its critical three-month review milestone.

Managed by Helios Technology, Fidelity includes the National Physical Laboratory, the UK’s measurement institute, and Thales Research Technology.

Each of Fidelity’s eight partners provides specific technical expertise, from industrial mathematics to design and systems engineering.

“We invented the atomic clock fifty years ago and are pleased to remain at the leading edge of Europe’s timing community,” said Dr John Davis, principal research scientist at NPL.

“Accurate time signals will enable Galileo to bring enormous commercial and civilian benefits not just to the UK and Europe, but to users across the globe.”

One nanosecond of time difference on a satellite is the equivalent to about 30cm on the ground, so highly accurate time is essential to the success of Galileo.

Even the best atomic clocks lose time. Monitoring and correcting these time drifts enable the accuracy of Galileo to be maintained. Precision time plays a fundamental but often neglected role not just in navigation, but also electricity distribution, the functioning of email and the Internet, deep space exploration and telecommunication networks.

Fidelity will create an operational prototype Galileo Time Service Provider (GTSP) to deliver UTC services to Galileo in time for its In-Orbit Validation due in 2008. UTC – Co-ordinated Universal Time – is the atomic realisation of Greenwich Mean Time. Fidelity will also prepare an institutional and operational migration path to a permanent GTSP.

“This is more than a technology project,” says project leader Ian Poyner of Helios Technology. “We are required to create a key piece of infrastructure for Galileo, combining the strengths of our European partners that will enable the Galileo test bed to fulfil its true potential.

“The lessons learnt in developing and operating the GTSP over the next three years will form a foundation of the full Galileo system that will operate globally for the next 18 years.”

The three-year Fidelity contract brings together timing laboratories from the UK, Italy, Germany, Poland and France.

A new facility is being developed at the French National Space Agency (CNES) in Toulouse to integrate the software and hardware design being developed at sites across Europe.