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Astrium Pdg Uk Doc. ID: TSTI2/HH/TN/18.23 Issue: 1 Date: 27/06/2018 Fuel TAO (Towards the All Optical satellite communications system) ESA Contract Nr. 4000117594/16/NL/GLC Executive Summary “© Airbus Defence & Space SAS 2018 - The copyright in this document is vested in Airbus Defence & Space SAS. This document may only be reproduced in whole or in part, or stored in a retrieval system, or transmitted in any form, or by any means electronic, mechanical, photocopying or otherwise, either with the prior permission of Airbus Defence & Space SAS or in accordance with the terms of ESA Contract No. 4000117594/16/NL/GLC.” Page 1 “© Airbus Defence & Space SAS 2018 - The copyright in this document is vested in Airbus Defence & Space SAS. This document may only be reproduced in whole or in part, or stored in a retrieval system, or transmitted in any form, or by any means electronic, mechanical, photocopying or otherwise, either with the prior permission of Airbus Defence & Space SAS or in accordance with the terms of ESA Contract No. 4000117594/16/NL/GLC.” Page 2 Table of contents Abstract ................................................................................................................................................... 7 1. Introduction ..................................................................................................................................... 9 2. State of the art ............................................................................................................................... 11 3. Market analysis ............................................................................................................................. 14 3.1 Space based communication systems .................................................................................... 14 3.2 Terrestrial communication systems ......................................................................................... 15 4. Identification of scenarios ........................................................................................................... 19 4.1 Considered scenarios .............................................................................................................. 19 4.2 Selection of scenario ............................................................................................................... 19 4.3 Scenario A: provide connectivity in case of lack of terrestrial network .................................... 20 4.4 Scenario B: provide redundancy in case of failure of terrestrial network ................................ 21 5. Architecture & roadmap of an all optical satellite system ....................................................... 23 5.1 On-board architecture .............................................................................................................. 23 5.2 On-ground architecture ............................................................................................................ 25 5.3 Roadmap for an all optical satellite system ............................................................................. 26 6. Conclusion .................................................................................................................................... 28 “© Airbus Defence & Space SAS 2018 - The copyright in this document is vested in Airbus Defence & Space SAS. This document may only be reproduced in whole or in part, or stored in a retrieval system, or transmitted in any form, or by any means electronic, mechanical, photocopying or otherwise, either with the prior permission of Airbus Defence & Space SAS or in accordance with the terms of ESA Contract No. 4000117594/16/NL/GLC.” Page 3 List of Figures Figure 1 : TAO study logic .................................................................................................................... 9 Figure 2 : system configurations considered in the TAO study ...................................................... 11 Figure 3 : Satellite technology evolution ........................................................................................... 14 Figure 4 : Evolution of connected home devices ............................................................................... 16 Figure 5: Illustration of Scenario 2 - All optical backhauling of white areas ................................ 21 Figure 6: Illustration of Scenario 1 - Redundancy of terrestrial network ..................................... 22 Figure 7: Difference between an optical amplifier and an optical repeater................................... 23 Figure 8: architecture of an all optical satellite system with on-board processing (repeater option) and associated TRL level for a 100 Gbps optical link ........................................................... 24 Figure 9: architecture of an all optical satellite system without on-board processing (amplifier option) ................................................................................................................................................... 25 Figure 10: Functional architecture of a ground station and corresponding TRL levels ................. 25 “© Airbus Defence & Space SAS 2018 - The copyright in this document is vested in Airbus Defence & Space SAS. This document may only be reproduced in whole or in part, or stored in a retrieval system, or transmitted in any form, or by any means electronic, mechanical, photocopying or otherwise, either with the prior permission of Airbus Defence & Space SAS or in accordance with the terms of ESA Contract No. 4000117594/16/NL/GLC.” Page 4 List of Tables Table 1 : synthesis on space based optical systems .......................................................................... 12 Table 2 : main mission characteristics ............................................................................................... 13 Table 3 : Non-GEO Communications Constellations Projets, 2017-2021 ......................................... 15 Acronyms and abbreviations Acronym Definition Airbus DS Airbus Defence and Space AIT Assembly, Integration and Tests EDRS European Data Relay System GEO Geostationary Orbit HAPS High Altitude Platform System HTS High Throughput System LEO Low Earth Orbit LTE Long-Term Evolution MAIT Manufacturing, Integration and Tests MEO Medium Earth Orbit OGS On Ground Station OTN Optical transport Network POP Point Of Presence “© Airbus Defence & Space SAS 2018 - The copyright in this document is vested in Airbus Defence & Space SAS. This document may only be reproduced in whole or in part, or stored in a retrieval system, or transmitted in any form, or by any means electronic, mechanical, photocopying or otherwise, either with the prior permission of Airbus Defence & Space SAS or in accordance with the terms of ESA Contract No. 4000117594/16/NL/GLC.” Page 5 “© Airbus Defence & Space SAS 2018 - The copyright in this document is vested in Airbus Defence & Space SAS. This document may only be reproduced in whole or in part, or stored in a retrieval system, or transmitted in any form, or by any means electronic, mechanical, photocopying or otherwise, either with the prior permission of Airbus Defence & Space SAS or in accordance with the terms of ESA Contract No. 4000117594/16/NL/GLC.” Page 6 ABSTRACT Although the first laser communication systems were demonstrated in space in the 1990s, it is only recently that the technology, reliability and economics of space based optical systems have combined with the need for more bandwidth to push them into operation. Developments supported by space agencies pave the way for a commercial use of optical technologies, which are planned to revolutionize communication network architectures by introducing a hybrid terrestrial/space options. In this context, the goal of the TAO study is to identify a relevant business case based on an all optical satellite system, to detail the corresponding system architecture and to assess the associated roadmap. Two missions have been selected among an initial pool of seven scenarios: - the white areas backhauling: 10 Gbps of aggregated capacity are sufficient to provide high speed connection to a local access network. This would be a temporary measure, to allow a terrestrial solution to come forward. - the redundancy of terrestrial network for isolated islands, landlocked countries or for any region with a lack of optical fibre redundancy: 100 Gbps class links are required to provide a useful redundancy of the terrestrial network. As in the previous case, the optical link will only operate during the time required to restore the connection. The two scenarios have technical, operational and commercial similarities. Indeed, they both: - Operate two bi-directional optical links: since data are carried in the optical digital format, no conversion is required to pass from the terrestrial to the space domains. Compared with a DVB system, this drastically reduces the complexity and the cost of the ground segment. - Manage end to end proprietary links: dedicated optical FEC can be implemented in each OGS, which avoids implanting FEC on-board. In this case the satellite has the same role than an optical repeater, which considerably simplifies the on-board chain - Operate an all optical link with limited capacity (< 100 Gbps), which relaxes implementation constraints and make possible considering a hosted payload option. - Use state of the art photonic components, 10 and 100 Gbps being terrestrial standards. - Operate during a limited amount of time, the corresponding business case
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