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Jump to: Mission Objectives, Mission Instrumentation, Mission Parameters, Additional Information

Mission Photos:
GIOVE-A Satellite GIOVE-B Satellite
GIOVE-A (Courtesy of ESA) GIOVE-B (Courtesy of ESA)
Mission Objectives:

Galileo is a satellite radio navigation system initiative launched by the European Union and the European Space Agency. Galileo consists of a constellation of 30 satellites and ground stations providing position information to users in many sectors (transportation, social services, justice system, custom services, public works, search and rescue, etc.).

Two experimental spacecraft were launched in 2005 and 2008 as part of the Galileo System Test Bed V2: GIOVE-A (Galileo In-Orbit Validation Element, formerly GSTB-V2/A) and GIOVE-B (formerly GSTB-V2/B). The objectives of this mission are:

  • to secure the Galileo frequency allocations by providing a signal in space
  • on-board clock characterization
  • MEO radiation environment characterization
  • additional experimentation

The GIOVE-A and -B satellites are equipped with LLR arrays to provide precise orbit determination. Both routine SLR tracking and occasional campaigns with more intense tracking will be required. By June 2006, a sufficient number of receivers were deployed to allow ESA to begin microwave orbit determination. Therefore, an initial SLR tracking campaign began in June 2006 and lasted for eight weeks; further campaigns followed with routine tracking currently in place. Predictions are based on these microwave-determined orbits; prediction accuracy is on the order of 30 meters. GIOVE-A tracking is comparable to GLONASS and GPS tracking (perhaps up to 40 percent more return energy than GPS).

A third satellite, GIOVE-A2, is under construction in 2007 for launch in the second half of 2008. The same company that built GIOVE-A will build this new satellite, basing its technology on that of GIOVE-A, with some enhancements.

Mission Instrumentation:

GIOVE-A has the following instrumentation onboard:

  • Phased array antenna of individual L-band elements
  • Signal generation units to create two representative Galileo signals
  • Two redundant rubidium atomic clock
  • Retroreflector array
Mission Parameters:
Expected Life: 2 years 2 years 2 years years
Primary Applications: Positioning Positioning Positioning Positioning
COSPAR ID: 0505101 TBD 0802001 TBD
SIC Code: 7001 TBD 7002 TBD
Satellite Catalog (NORAD) Number: 28922 TBD 32781 TBD
Launch Date: 26-Dec-2005 Mid 2008 26-Apr-2008 2009
RRA Size: 308mm x 408mm x 48 mm 308mm x 408mm x 48 mm 305mm x 305mm x 42 mm 435mm x 540mm x 53mm
RRA Shape: trapezoidal trapezoidal trapezoidal trapezoidal
Reflectors: 76 corner cubes 76 corner cubes 67 corner cubes 78 corner cubes
Size of Reflector: 27 mm 27 mm 27 mm 27 mm
Orbit: near-circular near-circular near-circular near-circular
Inclination: 56 degrees 56 degrees 56 degrees 56 degrees
Altitude: 23,916 km 23,916 km 23,916 km 23,916 km
Eccentricity: 0.002 0.002 0.002 0.002

Additional Information:

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