ESA

1
ESAs GSTB Programme

• GSTB-V1 is a ground system to test Galileos key
  algorithms using GPS data
• GSTB-V2 consists of a pair of satellites
• GSTB-V2/A (SSTL) now known as Giove-A launched
  in December 2005
• GSTB-V2/B (Galileo Industries) backup satellite
  in case of launch failures etc. Due to be
  launched in April 2006.
• GSTB-V2 contract worth 20M awarded to SSTL in
  July 2003

2
Giove-A Platform

• Platform
• Dimensions 1.3m x 1.3m x 1.4m (stowed)
• Wet mass 660kg
• Power generation Sun tracking arrays
• Sensors EHS, ASS, Gyro
• Actuators Wheels, Magnetorquers, Thrusters
• Pointing 0.55 pitch/roll required (3?), 0.1
  achieved 2.1 yaw required, 1.0 achieved
• Orbit determination NORAD, Laser ranging, GPS,
  reverse GNSS
• Propulsion 90 ms-1 ?v butane system
• TTC S-Band
• Avionics SSTL Enhanced Microsat

3
Giove-A Navigation Payload

• Custom payload designed by SSTL
• Payload items supplied by ESA through contracts
  with third parties
• Alcatel Espacio (Spain) Clock Monitoring
  Control Unit
• Norspace (Norway) Frequency Generation
  Upconvertor Unit
• Alenia (Italy) Wide-band Radiating Antenna
  System
• Laben (Italy) Navigation Signal Generation Unit
• Temex (Switzerland) Rubidium Atomic Frequency
  Standard (stable to 10 ns per day)

4
Giove-A Environmental Payloads

• MERLIN QinetiQ
• Cosmic-Ray LET Spectra
• Proton Flux
• Total Ionising Dose
• Electrons/ Deep Charging Currents
• CEDEX UniS/SSTL
• Cosmic-Ray LET Spectra
• Proton Flux
• Dose-Rate Induced Photocurrents

CEDEX Space Weather Monitor
5
Giove-A Experimental Payloads

• GPS Receiver SSTL
• Laser Retro-Reflector

SSTL Miniature Space GPS Receiver
Laser Retro-Reflector Array
CEDEX Radiation Monitor
MERLIN Radiation Monitor
GPS Receiver Antenna
6
Giove-A Payload Architecture

• Payloads Navigation, Environmental and
  Experimental

7
Giove-A AIT
Antenna
Payload Bay
Avionics Bay
Propulsion Bay
Giove-A Flight Model 1st Integration at the
Surrey Space Centre, University of Surrey, Summer
2005
8
Launch!

• Launch Day 28th December 2005 0519 UTC
• Soyuz launch vehicle from Baikonur
• Fregat upper stage to inject Giove-A into the
  correct Galileo orbit

9
LEOP

• Communications were established with the SSTL
  ground-station at the University of Surrey
  immediately upon separation.
• Telemetry received at Surrey, Bangalore, India
  and Kuala Lumpur, Malaysia, in conjunction with
  the 12m satellite tracking antenna at RAL, showed
  all systems were nominal.
• The solar arrays deployed perfectly, and initial
  operations were completed ahead of schedule.

10
First Navigation Signals

• Europes first Galileo navigation signals were
  transmitted by Giove-A at 1725 UTC on 12th
  January 2006.
• The signals were commanded on from Surrey and the
  Galileo signals were received by the 25m antenna
  at the CCLRC Chilbolton Observatory, Andover, UK
  and the ESA Earth-Station in Redu, Belgium
• The Galileo E5 and L1 channel signals were
  successfully decoded by a Galileo Navigation
  Receiver at Surrey...

11
Conclusions

• In July 2003 SSTL embarked on its most complex
  project ever the design and construction of a
  totally new 600kg satellite for use in Medium
  Earth Orbit.
• Surrey rose to the challenge and, just 24 months
  later, delivered the Giove-A satellite to ESA for
  environmental testing.
• The Soyuz launch from Baikonur was successful,
  and platform commissioning was completed ahead of
  schedule.
• On 12th January 2006, Giove-A met its prime
  objective of demonstrating a Galileo navigation
  signal in space.
• Giove-A already has been a remarkable success,
  and it will enable ESA to achieve their 4 major
  objectives with this satellite at relatively low
  cost.
• The Galileo system is on its way!