GRAS - Galileo Road Application Simulator

GRAS is a simulation and verification tool to support satellitepositioning and navigation technology and to particularly demonstrate the expected Galileo system and service characteristics at selected Points of Interest (POI) in the urban area.

Short Description

The objective of GRAS is to show quality improvements in terms of positioning accuracy of the future European Satellite Navigation System Galileo by simulating the Signals in Space (SIS) using the POLARIS tool and verifying the results by the ground truth verification tool GeoTracker.

In order to develop the Galileo Road Application Simulator, satellite visibility was simulated in the POLARIS tool under different space, ground and user segment constellations, i.e. GPS only, Galileo only and combined GPS and Galileo visibility at selected urban POIs representing different shading scenarios.

The plausibility test of the simulation enabled the verification of the simulation results and showed the true satellite visibility under real conditions in urban areas. The functionality of the developed Galileo Road Application Simulator integrated all results and consists of the following components:

  • A navigation bar for selecting the preferred urban Point of Interest.
  • The graphical design of the user position on the map as simulated with state-of-the-art simulation software available for PDA’s.
  • The illustration of the user position in the orthographic picture with integrated visibility mask.
  • The illustration of the user position in a three-dimensional angular perspective with highlighting the visible horizon.
  • User’s view illustrated by 360 o panoramic photo of the real urban environment.
  • The display of the simulation results of the satellite positioning accuracy and availability at the Point of Interest.
  • A link providing the summary project description, partners and data as well as software used.

The GRAS tool is available on CD-Rom that can be used without any additional installations of plug-ins or other software, therefore enabling a user-friendly and platform-independent usage.

Project Partners


ARC Seibersdorf research Ges.m.b.H. - Birgit Löcker


  • Communication & Navigation - Werner Oberegger
  • GeoVille Informationssysteme und Datenverarbeitung GmbH - Frederic Petrini-Monteferri
  • GMV S. A. - Angel Gavin

Contact Address

ARC Seibersdorf research Ges.m.b.H.
Birgit Löcker
A-2444 Seibersdorf