1. A Low-Cost Modular Platform for GEOSTATIONARY and NAVIGATION satellite missions Stuart Eves, Phil Davies, Doug Liddle, John Paffett, Martin Sweeting, Alex Da Silva Curiel Email: s.eves@sstl.co.uk, p.davies@sstl.co.uks.eves@sstl.co.uk, p.davies@sstl.co.uk Tel: +44 1483 683347 Responsive Space – LA - April 2004

2. Why GMP? A new, much smaller, platform family –Geostationary minisatellite platform (GMP) Designed to fill the market requirement for cost-effective, fast-response small geostationary spacecraft. The GMP family will target the missions with payload requirements of 90-260kg and 800-1500W The SSTL geostationary minisatellite (GMP) has been designed specifically to address the market requirement for a small,low-cost, rapid-schedule, geostationary platform.

3. Benefits of Modularity Reduced Cost - <$20m Rapid Response – Target time of 1 year to launch Reduced Risk – Flight proven hardware System Growth – Allows for demand change during system life Geographic Diversity – More options for slot coordination Robustness – Graceful system degradation in case of failure Technology Insertion – Opportunities to demonstrate new satellite technologies and services

4. GMP - Complementary not competitive SSTL GMP has been designed specifically to address lower end of the market: Intended to complement existing traditional GEO platforms and not compete with them The future could see small satellites used for proof of market, with larger spacecraft used to provide bulk capacity The GMP design allows clusters of satellites to be used as a coordinated asset

5. The GMP Family Platform variants –Two platform variants are planned Direct injection variant (GMP-D) Transfer variant (GMP-T) –GMP-D Designed to utilise low-cost secondary direct injection launch opportunities e.g. Proton, Atlas 5, Soyuz, Zenit, Angara, Dnepr Constraints – 400kg maximum launch mass –Results in limited payload accommodation capacity –GMP-T (under development) Designed for conventional delivery into GTO Includes propellant for transfer Allows increased payload capacity Constraints – Complement not competition –1500 W / 260kg payload limit

6. $17m (GMP-D) $24m (GMP-T) Target Recurrent Platform Costs Semi-autonomous ground station employing COTS hardwareGround Segment & Operations Flexible baseline architecture capable of supporting plug-and-play replacement and upgrade. 3-axis stabilised platform with fully autonomous station keeping. GPS and PRN ranging GMP-D: Hydrazine Mono-prop GMP-T: MMH/N2O4 Bi-prop GaAs/Ge Triple Junction Li-Ion, sized for payload eclipse operations Primary through payload Redundant through S-band Platform Avionics AOCS Orbit Determination Propulsion Arrays Battery TT&C None - full eclipse operation required up to 110kg (GMP-D) or 260kg (GMP-T) up to 1 KW (baseline), with upgrade can go to > 1.5kW Payload Operational limitations Mass carrying capability Power available Up to 7 year mission lifetime LEO, GTO, MEO, GEO, HEO Lifetime Operating Orbit Target - 12 months - Contract signature to launch readiness Production schedule GMP Specification

7. GMP – Payload Accommodation

8. Example GMP-D Payload Description: 6x Ku-band transponders Coverage: Regional Uplink: Single receiver cold redundant backup receiver G/T: 10dB/K Downlink: Six transmit chains Two cold redundant backup HPA’s Transponder bandwidth : 72 MHz Typical EIRP : 50 dBW TT&C: Continuous telemetry and telecommand feed Satellite Antennas: 0.5 – 0.7m Applications: Television, Direct-To- Home broadcast, Internet connectivity, VSAT, telephony, Etc.

9. GMP – AIT Modular design –Allows short duration programmes By permitting parallel manufacture and test Propulsion Bay Avionics Plate Payload Frame

10. GMP – Operations As with SSTL’s LEO spacecraft, GMP has sufficient on-board autonomy to provide the necessary payload availability without needing to resort to a traditional “24/7” man-in-the loop operations strategy: –Autonomy is distributed between on-board and on- ground systems –On-board systems protected by rad-hard safety monitor –Anomalies generate operator alerts via SMS/Internet

11. GMP 1 st Flight 2005 ESA GSTB-V2 –Precursor to European Galileo programme –Objective Secure frequency filing Measure MEO environment Demonstrate key payload technologies Provide Signal-in-Space for Experimentation –Requirements Two year mission lifetime Low cost, rapid schedule Ideally suited to a SSTL solution

12. GSTB Platform

13. GSTB Schedule Schedule driven by Autumn ’05 launch QSRPDR CDR IRR FRR TRR MR Design Manufacture Integration Environmental Test Launch QSR : 31/07/03 PDR : 27/11/03 CDR : 30/06/04 IRR : 23/08/04 TRR : 04/05/05 FRR : 10/08/05 LW : October 05 KO +5 +12 +14 +22 +25 +27

14. Other Payloads Studied In addition to FSS and Galileo, SSTL has assessed the suitability of GMP for: –Mobile (S-UMTS) coverage over a region the size of Europe –Bent-pipe and regenerative SBAS augmentation systems –Slot clouds using ISL

15. Conclusions In GMP, SSTL now has a responsive,low-cost ‘beyond LEO’ platform GMP extends SSTL’s low-cost engineering approach into new application areas: –Telecommunications –Navigation –Science Platform can also be used in MEO, GTO & LEO SSTL’s future developments will extend the capability and clusters of GMP could compete with the capabilities of traditional “big” satellites First flight of GMP will be ESA’s GSTB-V2/A in ’05 –Demonstrating GMP’s ability to carry complex payloads –Demonstrating the ‘rapid response’ capability… –…on a high profile mission

16. End Thank You!

17. GMP Avionics Architecture

18. GSTB Avionics Architecture