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                  The Galileo concept (copyright ESA/J. Huart)




                  Galileo                                               • experimental Galileo system time and
                                                                          steering to UTC/TAI
                  System Test Bed Version-1                             • orbit determination and time synch-
                  Following twelve months of successful ground-           ronisation, and signal-in-space accuracy
                  segment development operations for the                • integrity computation.
                  Galileo programme, the Galileo System Test Bed
                  Version-1 (GSTB-V1) routine operations were           The GSTB-V1 has also mitigated the risks
                  concluded on 22 December. The GSTB-V1                 inherent in the development of the operational
                  project supported investigation of the critical       processing facilities for the Galileo ground
                  performances behind the services to be                segment, bringing added value in terms of
                  delivered to users by the final Galileo system.       confidence, design consolidation and
                  The results of the experiments conducted will         accelerated schedule, by ensuring:
                  be fed into the development-phase activities          • actual measurements and comparison of
                  necessary for in-orbit validation of the system.        alternative algorithms in a realistic
                                                                          environment
                  GSTB-V1 consisted of a worldwide network of           • an appropriate Galileo timing-infrastructure
                  sensor stations collecting high-quality GPS             setup
                  observables at 1 Hz, an Experimental Precision        • calibration over an extended period of time
                  Timing Station, located at the Istituto               • early verification and tuning of simulators,
                  Elettronico Nazionale (IEN) Time Laboratory,            and the build-up of adequate analysis tools
                  providing the reference time scale steered to         • consolidation of the operational concept.
                  universal time and international atomic time
                  (UTC/TAI), and a Processing Centre located at         The next step will be a second Test Bed, GSTB-
                  the ESA/ESTEC in The Netherlands, which was           V2, geared to the launch of the first
                  used for the generation of navigation and             experimental satellite by end-2005, which will
                  integrity core products based on Galileo-like         allow experimentation on the signal-in-space
                  algorithms.                                           and the navigation payload, including onboard-
                                                                        clock characterisation.
                  The experimentation results have made it
                  possible to assess, in a realistic environment, the   In-Orbit Validation Contract
                  feasibility of some of the most important             Following the signing of the first contract in
                  assumptions and performance objectives for            July 2003 for two test satellites, known as GSTB-
                  the final Galileo system, including:                  V2, the Galileo programme took a further step


34   Navigation                                                                                          esa   Annual Report 2004
forward on 21 December 2004 with the signature         the management of
of a second contract concerning the In-Orbit           a fleet of sailing
Validation (IOV) phase. ESA and Galileo Industries     boats, including a
signed a 150 MEuro contract, as a first step           more efficient re-
towards signing an approximately 950 MEuro             sponse to calls for
contract covering the overall IOV phase.               assistance. Further
                                                       demonstrations in
The contract provides the basis and the                the Athens Olympic
technical activities necessary for in-orbit            environment
validation of the Galileo system. It gives             proved how useful
preliminary authorisation to proceed with the          EGNOS can be in
whole of this work, over a six-month period. It        the management of
concerns the management of the programme               a security company
and the choice of engineering systems and              by offering appro-
technical support required to maintain the             priate tools to the patrol cars and guards on      A prototype EGNOS-based
overall credibility of the scheduling and to           duty.                                              train-locating unit, which
                                                                                                          forms part of a system
ensure system coherence.                                                                                  known as INTEGRAIL,
                                                       Although first designed for aeronautical           installed in a locomotive
IOV involves the delivery of the first four            applications, EGNOS can also be used for           for test purposes
                                                                                                          (Courtesy of Bombardier
satellites in the Galileo constellation of 30,         railways, as was shown by trials in Belgium with
                                                                                                          GmbH)
along with a number of ground stations.                train positioning via satellite, providing both
Subsequently, the programme will enter its             safe and cost-effective solutions.
deployment phase, which will cover the entire
                                                                                                          Lance Armstrong crossing
ground infrastructure network and the launch                                                              the finishing line of the Alpe
of the remaining 26 satellites, which will                                                                d’Huez stage of the 2004
                                                                                                          Tour de France, tracked from
complete the constellation.
                                                                                                          the local EGNOS Control
                                                                                                          Centre (left)
EGNOS

Several demonstrations were carried out in
2004, based on the European Geostationary
Navigation Overlay Service (EGNOS), Europe’s
first step into satellite navigation, a service that
provides superior positioning information by
correcting the signals delivered by the                Another       remarkable        EGNOS
American Global Positioning System (GPS) and           demonstration in 2004 was the real-
the Russian GLONASS system. By offering better         time tracking of cyclists during the
accuracy with integrity information and greater        Tour de France. It was possible to
continuity of service, EGNOS can enhance the           pinpoint certain riders, calculate their
safety, reliability and efficiency of transport        positions and speeds, and measure
operations everywhere, from inland waterways           the gaps between them. This
to urban environments or railway networks.             represents a potential revolution not
                                                       only for cycling events, but also for
Demonstration projects on the River Danube in          other large sporting events where
Austria, and on the Yangtze River in China,            one wants to follow the competitors’
showed the practical value of adapting                 progress.
satellite-navigation technology to the needs of
inland-waterway transportation, improving              These EGNOS demonstration projects
safety and offering value-added services.              in 2004 clearly proved that, whatever
Another demonstration project, still on the            the application, be it on land, on water
water but this time off the Greek coast near           or in the air, satellite navigation can
Athens, showed how EGNOS can enhance                   surely make a difference!


esa   Annual Report 2004                                                                                    Navigation              35

								
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