Galileo Ground Mission Segment Architecture and Performances

Bernhard Kleine Schlarmann, Martin Hollreiser, Francisco Amarillo

Abstract:	The Galileo Ground Mission Segment (GMS) plays the major role in the provision of the Galileo world-wide navigation and integrity services with demanding levels of real-time performances availability, accuracy, continuity and integrity. The GMS is hosting all key functions of the Galileo global component, which are implemented in fourteen different types of elements in order to achieve the main Galileo mission objectives: Four of them, namely the Galileo Sensor Stations (GSS), the Orbitography and Synchronisation Processing Facility (OSPF), the Integrity Processing Facility (IPF) and the Precision Timing Facility (PTF) represent the main processing facilities of the GMS and they are in charge of determining all navigation and integrity data for each level of service (open service, safety of life service and public regulated service). The dissemination of the service data (including those captured from Service Providers) towards the Galileo satellites or towards Service Centers is executed by the Message Generation Facility (MGF) and the Up-Link Stations (ULS). While these first six facilities are designed to operate fully autonomously with a high reliability in order to ensure and to provide an uninterrupted service to all Galileo users, four other element types, namely the Ground Assets Control Facility (GACF), Mission Uplink Control Facility (MUCF), Mission Support Facility (MSF) and Maintenance and Training Platform (MTPF) cover the various operability needs, which comprise mainly basic technical monitoring and control of all GMS elements, on-line mission monitoring and off-line mission analysis. Two types of facilities (MKMF/PKMF) are in charge of data protection and key management as well as management of the various related security modules. A last element type, namely the Service Product Facility (SPF) is dedicated to the implementation of the exchange zone between the GCC and the external world. A Mission Data Dissemination Network (MDDN) with unique features is in charge of the world-wide interconnection of the GMS sites and provides a very low latency, high availability and continuity. The MDDN is monitored and controlled by the Ground Network Management Facility (GNMF). The GMS design and performances were reviewed in the frame of the Critical Design Review (CDR), which was successfully executed in second quarter of 2008. This paper provides an up-to-date overview of the main GMS design features as presented at this major Galileo milestone and gives an insight into the architecture formed by all those elements. Furthermore the paper addresses the key design choices and trade-offs, the level of redundancy and specific safety features and barriers fulfilling the needs for safety related applications. Finally the paper presents the major results of the GMS performances achieved for the CDR
Published in:	Proceedings of the 21st International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS 2008) September 16 - 19, 2008 Savannah International Convention Center Savannah, GA
Pages:	2505 - 2514
Cite this article:	Schlarmann, Bernhard Kleine, Hollreiser, Martin, Amarillo, Francisco, "Galileo Ground Mission Segment Architecture and Performances," Proceedings of the 21st International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS 2008), Savannah, GA, September 2008, pp. 2505-2514.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In