MULTI-LAYERED SATCOM SYSTEMS ( ARTES FPE 1B.131) – EXPRO+
10, September 2021

ESA Open Invitation to Tender: 1-10769
Open Date: 30/08/2021 09:40 CEST
Closing Date: 25/10/2021 13:00 CEST

Whilst the commercial Satcom sector has been dominated by the use of Geostationary orbits (GSO) from its inception, the use of Non-Geostationary Orbits (NGSO) has been a constant and steadily growing feature of the industry for some years now. Historically, Low Earth Orbit (LEO) systems served entirely separate markets and customers to systems deployed in GEO with little overlap between the two technology/application areas. E.g. Low data rate and voice services from Iridium contrasting with DTH TV Broadcast from SES. BothGSO and NGSO Satcom systems have their own inherent strengths: GSO systems can offer broad contiguous service regions, fixed groundantenna orientation, longer satellite lifetimes, a simpler frequency coordination environment, lower financial costs to achieve regional coverage, and lower maintenance/operational costs. Conversely, NGSO systems offer improved latency, significantly reduced pathlosses enabling miniaturisation of ground terminals, have the potential to provide truly global coverage, and support the maximum total system capacity within a given spectrum allocation.Until now, Satcom systems have chiefly been designed in isolation, i.e. without considering the co-existence of systems simultaneously operating in other orbits. In the future, a more integrated approach toSatcom system planning and design will likely emerge that focusses more on the end-customers’ communication needs and seeks to exploit the advantages of both GSO and NGSO orbits.Already, networks comprising diverse orbits, spectrum allocations, and technologiesare being formed via merger, acquisition, and organic growth in the satellite operator sector, e.g. SES absorbing O3b and Eutelsat’s ELO System. Tracking antennas capable of operating in dual frequency bands (e.g. Viasat’s aircraft mounted Ku and Ka-Band system and Intellian’s C and Ku-Band ground-based GEO/MEO tracking systems) are current commercial products. This convergence will likely continue; in the shorter term new systems are likely to consider mutual interoperability, i.e. common frequency bands and access protocols meaning that an individual user can switch’ between systems dependent on their short-term needs. I.e. instantaneous data rate needs, network congestion or failures, latency requirements, or security concerns. Further into the future, systems could be conceived as comprising a number of different orbital (and terrestrial) elements from the outset. Such systems would offer the further benefits of improving total spectrum utilisation and providing increased resilience to in-orbit failures.The proposed activity would therefore take the form of a system design exercise, attempting to define a future Satcom system topology that effectively exploits the benefits of a range of diverse space elements (i.e. GEO, MEO, and/or LEO). Such a system should be capable of supporting the fullrange of both current and future satellite service types, but with increased overall spectral efficiency and interoperability with both HAPS, UAV, and terrestrial based networks. As well as the overall network topology and space segment design, important considerations for the study would include:Access Protocols, Routing, and Network OperationsRouting or switching optimisation in a time variant’ network and access protocols capable of operating with a large variation in transmission delays would be important designchallenges, regardless of the whether nodes (i.e. spacecraft payloads) are transparent or regenerative. With such a dynamic system environment serving a wide range of users, a high degree of autonomous access, resource management, and network operation would alsobe essential, as would a spectrum allocation common to, and coordinated with, all system elements.Inter-Satellite Link (ISL) TechnologyNetwork topologies that require links between satellites operating in the same LEO orbital plane, and even intra-plane links, are an element of several current systems under development. ISLs between GSO spacecraft, whilst not currently widespread, appeartechnically viable with current technologies. Whilst high capacity links between LEO and GEO spacecraft have been reliably demonstrated by EDRS, a solution that can be economically scaled to the needs of an NGSO constellation has yet to be developed (one link perorbital plane would be required as a minima).Ground Antenna Technology With the advent of Flat Panel Array antennas, the potential for a single hub or feeder link terminal to simultaneously serve spacecraft in multiple orbits already exists. Current product lines are however best described as “enterprise-grade” solutions with price points restricting their deployment to niche applications. The availability of an affordable flat panel array antenna has been much anticipated for some years now. If the hoped-for breakthrough can be made in terms of volume and pricing for these systems, there will be major impacts to the way in which individual customers could be connected to the space segment. Additionally system architectures could be significantly impacted due to the change inthe economics of gateway antenna numbers and associated total feeder link capacity.The study should also consider whether the same overall goals might be achieved by facilitating the combination of system level elements from different owner/operators, e.g. collaborative combination of diverse GSO, NGSO, and ground-based components. The anticipated activity outcome would be an overall systemarchitecture, identifying both the potential benefits for end users as well as quantifying potential system efficiencies. Technologies needed to achieve such a system would be identified, potentially leading to follow on activity in terms of product development or demonstration projects.

Estabilishment: ECSAT
ECOS Required: No
Classified: No
Price Range: 200-500 KEURO
Authorised Contact Person: Florence Odette Jeanne Glandieres
Initiating Service: TIA-TFE
IP Measure: N/A
Prog. Reference: E/0501-01D – Future Prep 4.0.1
Tender Type: Open Competition
Open To Tenderers From: AT+BE+CA+CH+CZ+DE+DK+EE+EL+ES+FI+FR+GB+HU+IE+IT+LU+NL+NO+PL+PT+RO+SE
Technology Keywords: 8-C-II-Multidisciplinary Analysis
Products Keywords: 2-L-1-a-Omnidirectional, Helix, Horn, Parabolic, Phased Arrays / Platform vs Payload / 4-B-3-a-Telemetry and Telecommand equipment, Tracking, Ranging and Doppler measurement equipment, CODECS,…
4-B-5-Ground Station Monitoring & Control

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