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USING THE NEW L BAND MSS ALLOCATIONS - Study Group 8 Seminar on Tomorrow’s Technological Innovations Geneva, 9 September 2004. Marcus Vila ça Manager, Systems Engineering Advanced Systems Division. Inmarsat Background. Established in 1979 as an international co-operative
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USING THE NEW L BAND MSS ALLOCATIONS- Study Group 8 Seminar on Tomorrow’s Technological Innovations Geneva, 9 September 2004 Marcus Vilaça Manager, Systems Engineering Advanced Systems Division
Inmarsat Background • Established in 1979 as an international co-operative • Privatised in April 1999 • Owns and operates 9 satellites : 4 x Inmarsat 2 5 x Inmarsat 3 • Contract for 3 x Inmarsat 4 satellites signed in May 2000 • Firmly established in maritime, aeronautical and land markets • Customer base of over 320,000 users • Current services include messaging, voice and data • Global presence & network of suppliers of services and equipment • GMDSS
Inmarsat 1st Generation Space Segment Marecs Marisat 33 dBW EIRP 30 dBW EIRP 2 x 5 MHz bandwidth 2 x 5 MHz bandwidth 580 kg dry mass 360 kg dry mass 13.5 m solar array 2.2 m (w) x 3.8 m (h) Launch : A – 20/12/81 (22/08/96) Launch : 1 – 19/02/76 B – 09/09/82 (F) 2 – 10/06/76 B2 – 10/11/84 (23/01/02) 3 – 14/10/76
Inmarsat 2 39 dBW EIRP 2 x 20 MHz Processed Bandwidth 700kg Dry Mass 14.5 m Solar Array Span Launch: F1 – 30/10/90 F2 – 08/03/91 F3 – 16/12/91 F4 – 15/04/92
Inmarsat 3 49 dBW EIRP 2 x 60 MHz Processed Bandwidth 1000kg Dry Mass 20.5 m Solar Array Span Launch: F1 – 03/04/96 F2 – 06/09/96 F3 – 18/12/96 F4 – 03/06/97 F5 – 04/02/98
Inmarsat 4 67 dBW EIRP 10 dB/K G/T 2 x 126 MHz Processed Bandwidth 9 m deployable reflector 3000 kg Dry Mass 6000 kg Launch Mass 12 kW spacecraft power 10 kW payload power 48 m Solar Array Span Astrium’s Eurostar 3000 bus Major Subcontractors • TRW Astro • EMS • Alcatel • Boeing Launch : F1 – February 2005 F2 – July 2005
Inmarsat 4 Characteristics • Frequency Bands • Mobile Link @ L Band and Feeder Link @ C band • Transponders • Transparent bent-pipe, C/L, L/C, L/L, C/C & Navigational • Digital Channeliser/Beamformer • 630 x 200 kHz channels, dynamically allocated to beams • 256 beams • Mobile Link (RHCP, digital beam former) • 228 narrow spot beams for BGAN service (1.1 degree grid) • 19 wide spot beams for E&E service (4.05 degree grid) • 1 global beam • Feeder Link (RHCP & LHCP) • 1 global beam, dual polarisation
Amethyst Programme • Part of the ESA’s Artes 3 Line 4 study programme • Feasibility study focused on the changes required to the I4 payload design, to enable utilisation of the L band extension • Study lead by Astrium, supported by Inmarsat • Scenario 1 : Modification of I4 flight model 3 (“FM3”) • 1A - Minimum Changes • 1B - New DSP • Scenario 2 : Procurement a fourth spacecraft (“FM4”) • 2A - New DSP • 2B - Enhanced SSPA’s • Main Outputs: Design Solutions, ROM Cost & Development Plan
Scenario 1 – Other Equipment Changes • L Band Feed • New diplexers • Feed element retuning • ONet’s • New output filters
Scenario 2 – Other Equipment Changes • L Band Feed • New diplexers • Feed element retuning • ONet’s • New output filters • New SSPA’s • Increased output power
Planned Spectrum Activities • Studies into the use of the new bands and related sharing studies • Participation in the work being carried out by WP8D. • Regulatory study of the new bands • Assess the use of the new bands by existing terrestrial services, and the possibility of utilization of those bands for the provision of MSS in various countries, concentrating in Region 1 and Region 3. • Satellite antenna discrimination • Analyse the impact of PFD limits on the service coverage area by taking into account satellite antenna discrimination performance.
Conclusion • The MSS L Band extensions offer a great opportunity to significantly increase the capacity of MSS satellites. • The modifications required to the baseline Inmarsat 4 satellites to allow service provision in the new bands are significant, but can be kept within limits that allow reduced risk and lower cost and schedule impact. • A comprehensive study on the utilisation of the extended L band by existing services will be carried out, to provide an accurate picture of the current situation and of any possible constraints.