This presentation will introduce this session which is devoted to platform and communication space-to-ground technologies for future Earth Observation (EO) systems. As starting point, an overview of the Technology strategy in ESA for EO will be provided, but aspects related to Microware and Optical Instruments for EO will be further elaborated in complementary sessions within the same Space Technologies Theme.

A very important point of this EO Technology Strategy is related not only to de-risking technologies and enabling new and more performing capabilities such as allowing the downlink of higher data volumes, but also to reducing recurring costs and to the faster adoption of innovative technologies. In this respect, the standardization of the platform, enabling the availability by multiple supplying sources of not only full platform sub-systems, but also of their modules and their easy replacement, is of paramount importance. The adoption of spin-in technologies e.g. COTS and new engineering approaches to adopt is part of this game changer. Higher lifetime and more flexibility (e.g. with more on-board reprogrammable FPGAs devices) are other very important points that require technology advances.

All these aspects become more and more important in a context of system-of-systems, and the coexistence of institutional EO flagship satellites acting as reference and complemented by NewSpace constellations of less costly and smaller and possibly smarter spacecrafts providing the required temporal revisits, thanks to more integrated and miniaturized technologies. This opens a number of additional requirements on more autonomous platforms and operations, as well as on synchronization and co-registration aspects. More distributed and scaleable ground segments are expected to support this paradigm shift. On the other side, all this growth in capability to observe climate changes needs to be supported by cleaner and demisable technologies.

The presentation will close with specific examples of game-changing technology developments in for example electronic components, or related to specific platform sub-systems like the data downlink communications or the game-changer Advanced Data Handling Architecture (ADHA) project, which will be further complemented by the other presentations in the session, by Large Scale Integrators but also by ESA regarding clean space and ground technologies.

AstroBus is Airbus' LEO avionics product. It comprises a suite of flight hardware, software, documentation, test benches and tools, implemented and managed as an avionics product. It is continuously maintained and adopts improvements/lessons learned from individual projects, shared and addressed for the benefit of current and future projects. Projects based on an avionics product benefit from proven elements already developed, validated and flown together. This limits non-recurring development costs, and offers attractive recurring costs. This also brings savings in verification activities, software development and validation, procedures, and testing platforms.

AstroBus is being used on many Airbus export or commercial EO missions and several ESA missions since around 2007. Different variants have been in operation with a large level of commonality in the equipment suite and software, as well as tools, documentation and processes.

Following an initiative to rationalise the product variants to create a more harmonised and efficient overall product, and supported by ESA’s 2018 Standard EO Platform study, a new unified reference is currently being implemented for Copernicus HPCM on LSTM and CRISTAL missions. The Generic Platform study gave Airbus a valuable forum to clarify and fully understand generic Copernicus requirements. Adaptations to for instance File based operation, CFDP (CCSDS File Delivery Protocol) or PUS-C require additional software functionality and some limited improvements to the OBC used in all AstroBus missions. Furthermore, new equipments have been added to the portfolio, integrated and qualified at avionics product level with the aim to increase the flexibility to the demands of different missions, technically or industrially – so, for example, double sourcing and SME participation already available on AstroBus, have been strengthened thanks to Copernicus HPCM missions. It also brings new technologies on the communication to ground.

For future ESA EO Future missions, Airbus intends to propose ESA to get full benefit of the Astrobus product. Additionally this will also include upgrades from the on-going developments such as the ADHA (Advanced Data Handling Architecture), which will bring further modularity and competitiveness to the platform product.

Besides, Airbus has also developed a highly competitive COTS based avionics for small platforms needs, which completes the Astrobus Product line.

OHB’s Standard Earth Observation Platform, Eos, serves the current and future needs for LEO Earth observation applications. Eos has been developed, among others, in the frame of the ESA Copernicus Standard Platform Study and will be implemented first for the Copernicus mission CO2M. The Eos platform is founded on common and well-established state-of-the-art technologies, thereby providing the opportunity of a fast track and low risk platform adaptation to different mission needs. The essential element of Eos is its standard avionics core, capable of implementing File Based Operations and the associated developed SCSW with its PUS-C customization.
With the ever increasing demand for faster and more comprehensive data and new instruments transferring data at a speed of more than 1Gbps, an evolution in the platform avionics is essential to occur to keep serving the Earth Observation missions.
For the next generation of Eos, OHB is investigating multiple aspects to meet future mission needs, such as:
• a more centralized avionics architecture, where multiple SW functionalities are combined into one on-board computer (e.g. GNSS SW, Star Tracker). Therefore assessing high performance multi-core processors.
• Control & Command interfaces to match the high data rates
• Implementation of a scalable standard backplane as designed in the Advanced Data Handling Architecture.

To meet in particularly the high data rates, a new very high-speed data link has been introduced named SpeceFibre designed specifically for on-board spacecraft adoptable as on-board data handling protocol in next generation space missions, from earth observation to science satellites.

SpaceFibre is able to operate over fibre-optic and electrical cable and to fulfil a data rate of 6.25Gbps together with the possibility to use multiple Virtual Channels over the same physical link, each one configurable with flexible Quality of Service (QoS) parameters (priority level, reserved bandwidth, and assigned time-slots). This would also bring to a great harness reduction.
SpaceFibre provides three interfaces to the user application:

• A packet interface used to send and receive packets.
• A broadcast message interface used to broadcast short messages over the SpaceFibre network.
• A management interface used for configuring, controlling and monitoring the status of the SpaceFibre interface.

The presentation will also introduce complementary platforms to Eos available in the OHB group, that can be used especially for Earth Observation new space missions and constellations ranging from a platform mass of 50 – 250 kg. A brief product description will be given as well as some examples of implemented mission such as the Arctic Weather Satellite (AWS) and the European IOD/IOV Satellite (EIS).

Following an initiative to rationalize the LEO platform product line in Thales Alenia Space, our M.I.L.A platform product line has been defined as the new European platform solution to address the high end LEO market. M.I.L.A stands for Multiapplication Innovative and moduLAr platform. As the Thales Alenia Space European platform solution, this platform product line can be proposed by each TAS entity as primeship : Thales Alenia Space France, Thales Alenia Space Italy or Thales Alenia Space UK. Each entity is in position to propose this platform product line under its satellite primeship and instantiate independently and with a full mastery the product. This solution has been contracted for the three Copernicus expansion missions CHIME, ROSEL and CIMR with under Thales Alenia Space France prime for CHIME and Thales Alenia Space Italy for ROSEL and CIMR. This platform product line is based on a building blocks approach to manage a large variability and scalability, such as platform mass 300 kg up to 3T, power capacity up to 6 KW and lifetime up 12.5 years. Variability of the product line covers TTC in X band, gyro or gyroless AOCS, modular power architecture …. This allows it to cover any kind of payloads including optical, radar or others. The development has started in 2018 and is running with the core qualification foreseen end 2023. Effectiveness and competitiveness of the solution has been implemented through product line engineering methods, innovation and state of the art technical solutions. The variability covers also the supplier list where some dual supplier scheme are possible without impact. The development is managed with a standalone project that owns the development of the product line with its first instantiation for the three Copernicus missions. This project named our “common platform” steers the M.I.L.A product line platform development and also the common solution developed for PDHT equipments. As a transnational team composed of French and Italian engineers manages the current development. The roadmap of the product line foresee electrical propulsion, AI, autonomy, and also Digital technologies... Thanks to its building block approach and flexibility, the use of this product line is not limited to Earth Observation but is foreseen also for Exploration and Science missions.

ESA CleanSpace, since its creation in 2012, has been proving the relevancy of its mandate - to maintain Europe’s leadership in innovating for a safer and cleaner space environment - with notable achievements such as the first ever active debris removal mission planned for launch early 2026, the set-up of the first worldwide frame for space ecodesign and the maturation of many technologies to manage spacecrafts’ end-of-life.

As part of its ecodesign branch, ESA CleanSpace has carried out a significant number of Life Cycle Assessment (LCA) studies covering different elements of a space mission (space, ground and launch segments) through its entire development sequence (phase A to phase E), allowing quantification of their environmental impacts on Earth. The LCA ¬is a standardised methodology (ISO 14040 and 14044) used to assess the environmental impacts of a product, process or service across all its stages and according to multiple environmental indicators (ozone depletion, resource depletion, global warming, human toxicity, etc.). ESA has pioneered the use of the LCA methodology with the objective to support the required evolution of space missions in response to the environmental regulations and challenges. Up-to-today, the ‘Space system Life Cycle Assessment Guidelines’, developed based on the results of LCA studies carried out at ESA and published by the Agency in 2016, are still the only guide to apply LCA to space activities world-wide. During the presentation, ESA will give a brief overview of the document as well as an introduction to the ESA developed LCA space database.
Further than just a ‘Green appeal’ approach, ESA has created some serious and significant knowhow in implementing LCAs in its own projects such as Ariane 6 or the Copernicus Expansion missions.

The second branch of CleanSpace tackles the reduction of debris in space. Proper management of End of Life (EOL) of satellites and launcher upper stages is key for the sustainability of space activities. Through the CleanSat initiative Europe has gained in the last years the competitiveness edge in several areas related to management of EoL, e.g. design for demise and passivation. This is a growing new market for space technologies, as Space Debris Mitigation (SDM) requirements embedded in the ISO24113 are evolving and now broadly applicable to institutional and commercial missions.
The Agency keeps thinking ahead of what is strictly required by the SDM requirements to ensure the competitiveness of the European space sector. A good example of this principle are the passivation solutions set forth by ESA. Every spacecraft operating in Earth orbit is required to deplete or make-safe all the energy stored on board (passivation) to avoid break-ups in orbit. As a showcase of the agency’s commitment to clean space, Copernicus Expansion missions are also requiring power passivation to be implemented even if the mission baseline is to perform a controlled re-entry and therefore passivation is not strictly needed.
In-Orbit Servicing is undergoing a very rapid development. In the scope of End-Of-Life, ESA has adopted a proactive approach towards Design for Removal i.e. prepare satellites to ease their capture and removal from orbit through an external service. In fact, the Copernicus Expansion missions will include features that will ease their removal from orbit in case of failure in-orbit. ESA will present the solutions currently under development to support the management of satellites including their removal with a particular focus on those planned to fly onboard EO missions in the coming years.

(R)evolution of EO satellite communications

Satellite communications for Earth Observation applications have been after some time a mature market with well established technologies. S Band for TT&C communications and X Band for the download of payload data are well established and this capacity is presently offered by many commercial operators.

Despite the high capacity of Earth Observation satellite links, compared to other satellite links, new missions require even higher communication capacity and the development and implementation of new technologies capable to download the ever-increasing amount of data captured by the various spacecraft instruments.

The presentation will introduce a quick overview of the present systems, to set a reference point. Then new technologies that are under development and implementation will be quickly introduced, indicating their benefits to the EO users. The following technologies are presented among others:

• Consolidation of K Band Links
• Weather forecast operations
• Variable Coding and Modulation/Adaptive Coding and Modulation
• CCSDS File Delivery Protocol in a distributed setup specific to Earth Observation
• Disruption Tolerant Network
• A full end-to-end communication protocol stack for a variety of Earth Observation scenarios
• Scalability and automation of operations for constellations
• Optical communications
• New Frequency Bands

Missions already under development like Copernicus Expansion (or HPCM) already rely on the timely implementation of many of these technologies. Other elements point at more distant dates, but are already in the roadmaps of future EO communication systems and shall be considered.

In the context of system of systems combining institutional and New Space missions and constellations, the ground segment shall evolve towards higher levels of automation, scalability, modularity and interoperability enabling growth thanks to more efficient operations.