GIOVE-A, the first satellite in the Galileo satellite navigation system celebrates 27 months in orbit this month, marking the completion of its nominal mission lifetime. The European Space Agency (ESA) has confirmed that the pioneering Medium-Earth Orbit satellite is a “full mission success” and has contracted SSTL to continue operations for an additional year as the satellite continues to perform and provide valuable Galileo services. Under a 28M euros contract, the 660kg satellite was developed by SSTL for the ESA.

The primary mission was to secure the Galileo frequency filings at the International Telecommunications Union. The satellite also played a crucial role as a test-bed for the Galileo payload units, providing a representative signal-in-space for ground-based experimentation with Galileo signals and characterizing the radiation environment for the Medium Earth Orbit which will be used by all future Galileo satellites. Following successful launch and commissioning, the GIOVE-A team undertook an intensive six-week payload in-orbit test campaign using the 25m dish at the Science Technology and Facilities Council Chilbolton station. Through these activities ESA was able to claim the frequency filings three months before the license expired.

Since commissioning the satellite has achieved a remarkably high operational availability with signals being broadcast for 99.8% of the time over the last year. The primary atomic clock, fundamental to all future Galileo satellites in providing highly accurate positioning and time reference signals, has been operating continuously since June 2007. Thirteen sensor stations around the world are used by ESA to track GIOVE-A and GPS navigation signals and these have demonstrated that Galileo will be a highly accurate navigation system. www.gpsdaily.com

The ESA says the GIOVE-B satellite will soon leave the ESA’s European Space Research and Technology Centre (ESTEC) in Noordwijk, the Netherlands, where it is undergoing final preparations. It is scheduled to be launched into orbit from Baikonur aboard a Starsem Soyuz/Fregat launch vehicle on April 27. The second Galileo satellite has completed its pre-launch testing.

GIOVE-B will test novel, key technologies for the Galileo system, such as the highprecision passive maser clock and the triple-channel transmission of navigation signals. Instruments onboard the satellite will measure the radiation and spacecraft charging environments. Following on from GIOVE-B, the first four satellites of the operational constellation are under development. They are scheduled for launch in 2010 and will enable a systemlevel verification of the Galileo design.or NPA (non-precision-approach) or for rail ETCS (European train control system) are required and will be applied for. It seems to be a more sophisticated scenario requiring suddenly two certifications instead of one and just adding complexity. Looking to figure 3 the advantages of this approach become obvious. Without a generic certification for the Galileo SIS each domain would have to include in their domain specific certification for any application all relevant components. They will have to ensure the reliability and availability of the Galileo system, validate the integrity signal and only thereafter can work on the requirements from their own application. The validation and verification of the Galileo SIS does not only increase the workload for the certification body within the domain but will also result in continuous efforts in all companies contributing to any phase of the Galileo system, like design, deployment, operation or maintenance. With the new multimodal certification approach these efforts are dramatically reduced for all engaged parties, as only for the Galileo SIS certification the suppliers of goods or services to the Galileo system have to participate and to provide the necessary information. Within a domain the efforts are reduced as during the certification process only the application specific requirements have to regarded based on the one time acceptance of the certificate for the Galileo SIS or for the interface of the reference receiver. Thus the new approach of a multimodal certification reduces the duration of a domain specific certification and perhaps more important reduces significantly the costs for the overall certification process. As risk and costs are reduced, products and services earlier available for market entry, this should result in total in a lower market entry level broadening the market for service provider and manufacturers.

Now coming back to the initial question if certification of the Galileo system is only driven by bureaucracy in the EU, one can say that the certification of Galileo SIS actually is a market enabler to allow more companies to profit with their services and products from Galileo. In total the end customer finally will have a wider range with lower prices to choose from.