Participation of the Institute in the Development of the Galileo Satellite Navigation System
Author: Prof. a.D. Dr.-Ing. Exzellenter Emeritus Bernd Eissfeller
In February 1999, the European Commission published a communication entitled “Involving Europe in a New Generation of Satellite Navigation Services”. This communication presented the Commission’s strategy for establishing a European satellite navigation system called Galileo. Due to the ambitious schedule, there was enormous pressure to solve technical problems, especially with regard to the definition of Galileo signals.
On account of the work it had carried out since 1983 (appointment of Professor G. W. Hein to the University of the Bundeswehr Munich), the Institute of Space Technology and Space Applications was an important center for the advancement of global navigation satellite systems (GNSS) in Europe in the year 2000. With this expertise, the Institute has long played a leading role in GNSS for ministries, industry, and space agencies (German Aerospace Center, European Space Agency, European Commission). It continues to play this role at the national and the European level in various working groups.
CSI Working Group (Compatibility, Signals, Interoperability)
The CSI (Compatibility, Signals, Interoperability) Working Group grew out of the European Signal Task Force, which was founded in the year 2000. A pressing problem in the development of Galileo was the allocation of suitable frequency bands in the L band which are compatible with the American GPS and the Russian GLONASS systems. In a second step, the digital signals for the services of Galileo were defined in detail. The working group led by Professor Hein was asked by the German Federal Ministry of Transport and Digital Infrastructure and the DLR to represent the German position in this field. On the basis of cooperation with the French Aeronautics agency CNES and the MoD and the British defense research institute DSTL, a signal structure was found which was acceptable for the United States. At an EU-US summit in Ireland (in 2004), the Commissioner for Transport Loyola de Palacio and the US Secretary of State Colin Powell signed an EU-US agreement regulating the joint use of frequencies by Galileo and GPS. Based on this agreement, a technical EU-US working group at UniBw M developed a joint signal in 2006. The signal is what is known as a multiplexed binary offset carrier (MBOC), which is used both for the open service of Galileo and for the civilian GPS III signal. The Signal Task Force was renamed the CSI Working Group in 2009. In Germany, work is being carried out by Professor Eissfeller and Professor Pany, in cooperation with the DLR Institute of Communications and Navigation.
CS Working Group (Commercial Service)
Following initial experience with IOV satellites (in-orbit validation), various sub-systems of the Galileo system had to be optimized. As part of this re-profiling, it was also necessary to reorganize the commercial service. The CS (Commercial Service) Working Group has been working on this problem since 2012. Professor Pany and Professor Eissfeller (retired) have been involved as technical experts on the German side. Work has progressed considerably. The commercial service will offer a high-accuracy service (HAS) with dm accuracy and a robust service with authentication. These improvements are currently being implemented in the ground and space segment of Galileo G1G (first generation of Galileo).
EE Working Group (European GNSS Evolution)
In 2015, it was widely agreed that Galileo must be further developed, i.e. a second generation (G2G) was necessary. For this purpose, the European Commission set up the EE (European GNSS Evolution) Working Group. This working group enables the 27 EU member states to represent their interests with regard to the development of G2G. The EE WG also promotes communication among the parties involved. Important documents for the development of G2G such as the High Level Document (HLD) were developed. The EE WG also participates in technical review processes in the G2G program. Professor Eissfeller was appointed as a technical expert who advises representatives of the German Federal Ministry of Transport and Digital Infrastructure and DLR Space Administration in the working group.
In terms of organization, the working groups are attached to the EC European GNSS Program Committee as advisory units.
Lead image: Brussels – where the working groups meet (© iStockphoto / LisaValder)