1. The Galileo System - Predicting Performance and Producing Simulated Data for Experimental Purposes Dr. Frank Zimmermann November 2006

2. Overview • Introduction • Galileo Simulation Capabilities (GSSF) • Validation of GSSF • Example Results • Support to Application Development • Summary Technical Excellence . Pragmatic Solutions . Proven Delivery

3. Overview on Galileo Activities at VEGA • Galileo System Simulation Facility (GSSF) • Galileo Ground Mission Segment Assembly, Integration & Verification Platform (Galileo GMS AIVP) • Galileo Constellation Simulator (CSIM) • Galileo Operations (GSTB V1 & V2, GaIn Operations Manager) • Galileo Test and Development Environment (GATE) • Co-operative Networks for Intelligent Road Safety (COOPERS) • Shareholder of Galileo Centre in Darmstadt (CESAH) (initial) prime objective Application Operations Verification Definition

4. The Galileo System Simulation Facility (GSSF) Galileo • Independent, global, European satellitenavigation system • For civilian applications & interoperablewith GPS GSSF • Simulation environment that reproducesthe functional and performance behaviourof the Galileo system • Offers the necessary flexibility and functional scope to support Galileo system simulation needs during the entire program life cycle. • Developed on behalf of ESA/ESTEC by an international consortium led by VEGA • Validation has received prime attention (also independently by ESOC). • Visualisation supported by IDL (CREASO)

5. GSSF – Simulation Capabilities • GSSF provides a single simulator that uses alternative models depending upon the type of analysis the end-user wishes to perform (more flexibility than traditional simulators): • Service Volume Performance Analyses (navigation and integrity performance over longer time periods and over large geographical areas). • Raw Data Generation (Galileo and GPS raw data for experimental purposes: RINEX observation, IGS SP3) • Simulation of the nominal system and its various degraded modes (failures of elements)

6. GSSF – Model Components • Space Segmentsatellite models • Environmentmain perturbationson satellite signal • User Segmentuser receivers andinternal algorithms • Ground Segmentrequired GS models(GSS & ULS)

7. GSSF Validation • GSSF has been rigorously validated. • SVS Validation: • Against simulated data from trusted sources • RDG Validation against real data: • RINEX files from Kourou were extracted from the GSTB-V1 test data set together with IGS ephemeris and clock files. • Code, carrier and Doppler measurements as simulated by GSSF RDG were compared with those obtained from the real Kourou data (stepwise approach). • ESA/ESOC have carried out an independent validation of GSSF • Successful IGS Processing and 64 mm RMS orbit fit over 24 hrs • The GSSF Raw Data is a valid representation of real measurement data.

8. GIOVE-A GIOVE-A GPS • Successful GSSF validation with GPS measurements • GIOVE-A measurements provided by ESA will now be used to further calibrate GSSF RDG • This will not affect the environment but satellite-specific models(e.g. acceleration due to solar radiation). GEO (EGNOS)

9. Signal in Space Monitoring Accuracy (1) • Nominal SISMAfor Galileo on aGSS network • Representslevel of accuracyin monitoringsatellite positions

10. Signal in Space Monitoring Accuracy (2) • Nominal SISMAfor Galileo on aGSS network • Subject to twostation failuresover North America • SISMA degradesaccordingly

11. Ground Station Visibility (1) • Visible GroundStations for a35 Station Network

12. Ground Station Visibility (2) • Visible GroundStations for aNetwork subject to2 failures • Reduced tominimum of 5 overNorth America

13. Space Based Augmentation Systems (1) • GSSF supports the analysis of stand-alone GPS/SBAS systems as well as GPS/SBAS combined with Galileo • Example: Compare visibility and navigation system precision with and without SBAS support: EGNOS: INMARSAT 3 F2 (AOR-E) ESA ARTEMIS INMARSAT IOR-W (III-F5) QZSS & WAAS • UERE budgets drive NSPcalculation.

14. www.jaxa.jp www.nict.go.jp The Japanese Quasi-Zenith Satellite System • QZSS is to cover both Japan and Australia, • To maintain continuous visibility at high elevations (urban canyons) • Three satellites moving in different orbits but following the same relative track.

15. Space Based Augmentation Systems (2)

16. Space Based Augmentation Systems (3)

17. Space Based Augmentation Systems (4)

18. Space Based Augmentation Systems (5)

19. Space Based Augmentation Systems (6)

20. Instantaneous Regional Integrity Risk

21. Instantaneous Availability of Integrity

22. External Regional Integrity Service (ERIS) GSS Sites (Network of Stations) Station List: Site# Location Longitude [deg] Latitude [deg] 1 SEOUL 127.00 37.70 2 PUSAN 128.93 35.18 3 CHEJU 126.50 33.50

23. Safety-of-Life User (Aircraft en-route)

24. GSSF Raw Data GenerationExample • Effect of a clock jump, imposed as a Feared Event during the simulation on a Galileo Satellite observed at a Galileo Sensor station (Kourou). • The clock jump is defined by an additional bias of -0.0003 s applied at30 min after the simulation start time. Due to environmental delays on the signal and clock offsets Jump of 90 km

25. COOPERS(Co-operative Networks for Intelligent Road Safety) Integrated EU-Project with the following objectives: • Establish methodology for the integration of traffic control, traffic management and traffic information systems • Develop cost-efficient and advanced roadside and vehicle-side sensors and positioning-based situation-dependable driver assistance system (OBU) • Evaluate whether such methods will meet the overall target to improve safety • Assess what additional value can be achieved by Galileo for robust positioning, applying measurement campaigns and calibrated simulation using GSSF • Kick-off in February 2006 (40 partners, initially for 18 months with a possible extension towards 4 years, co-funded by the EU)

26. Simulation of Mobile Users • GSSF supports the simulationof mobile users: • Ground-based vehicles • Aircraft in flight • Satellites in LowEarth Orbit (LEO) • Errors such as clockfailures can be simulatedalong the trajectories.

27. Experiment (pwpSystems) • OBU Prototype Development • Sensory & • Positioning Algorithms • Measurement Campaigns • Optimise combination of sensory and algorithms • Evaluate potential for performance improvement applying Galileo Cooperation for Robust Positioning Simulation (VEGA) • Extensions to GSSF • Interface to or Integration of OBU Model • Validation & Calibration for Reference Measurements (GPS) • Simulation with Galileo GPS-Performance (ESOC) • Provision of up-to-date GPS Performance Data • Support to OBU Modelling (Algorithms) • Support for Validation & Calibration of Simulation

28. Summary & Main Strengths of GSSF • Rigorously validated against real data or trust-worthy simulated data • Specifically tailored towards the needs of the Galileo community • Is being maintained by VEGA on behalf of ESA • Can be further upgraded to match evolving requirements • Updates to SVS capability successfully completed recently(Inclusion of Galileo Integrity Concept) • Galileo performance assessment is currently ongoing on behalf ofESA and in preparation of Galileo CDR in June 2007. • RDG calibration with GIOVE-A data is ongoing. • Approx. 300 licenses have been granted up to now by ESA worldwide

29. www.gssf.info www.vega-group.com frank.zimmermann@vega.de Consulting and Technology Technical Excellence . Pragmatic Solutions . Proven Delivery