Communication links between GNSS satellites are required if the constellation shall operate for an extended time without ground contact. Under such circumstances, jamming resistance is considered a critical requirement and optical links can provide the ultimate protection from ground-to-space jamming. At the same time, low cost, high reliability and small size, mass and power are important to be implemented on a GNSS constellation. The activity shall review the requirements on intersatellite links based on the GNSS architecture.

Carrier phase measurements are more precise than pseudorange measurements and are used for high precision services. The quality of the carrier phase measurements influences directly the Galileo/EGNOS Ground-Segment navigation and integrity algorithms output quality, as well as the GPS/Galileo professional and mass market user positioning accuracy. Unfortunately, phase tracking can be severely stressed under ionospheric scintillation (under severe scintillation, phase may change too fast for being tracked by the receiver).

Experience shows that shock specifications for release systems provided by suppliers rely on different test methods and test setups. As a consequence the specified SRS are not comparable and compliance statements given in proposal phases can still impose some risk. The selection of the release system thus strongly depends on individual experience and heritage.The objective is the definition of a standardised test setup for release systems, are the generation of a shock test database which includes most used releases systems (pyro and non-pyro).

The objective is to automate the generation of database editor MMIs resulting from a formally specified data-model. The data model is constructed in line with a domain ontology (prepared in an existing approved TRP activity) which removes ambiguity in terminology and data content. It is refined through the tailoring of E70-41A (packet utilisation standard). This will enable the automated generation of user interfaces to M+C AIT databases according to project specific space-ground ICDs.

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Current optical design of optical instruments is based on conic or aspheric surfaces of revolution (both on-axis and off-axis). Free-form surfaces (surfaces with no axis of symmetry) can now be manufactured thanks to recent advances in Single Point Diamond Turning. Despite this technological breakthrough the theory is unfortunately not at the same level. Free-form surfaces cannot be represented properly in an optical design software and cannot be used for efficient optimisation algorithms.

The ASTERM ablative heatshield material has recently been developed (under Astrium RD and TRP-DEAM) and is currently in pre-qualification (under MREP-DEAM2). This development is specifically tailored for application on the Earth return capsule of sample return missions.

Studies on high-sensitivity Rx have already focussed on weak-signal (e.g.

The Serial Peripheral Interface Bus or SPI bus is a synchronous serial data link de facto standard, named by Motorola, that operates in full duplex mode. Devices communicate in master/slave mode where the master device initiates the data frame. Multiple slave devices are allowed with individual slave select (chip select) lines. Based on the result of two running TEC-EDD activities (Modular RTU - GSTP, Standardization of Digital interfaces - TRP) this activity will prototype SPI protocol(s) and physical layers for space applications.

The starting point of the activities was the matching performance of a single element InGaAsSb detector, grown on a low cost GaAs substrate, reported by the University of Lancaster. GaAs substrates are low cost and available in large areas, making high pixel count arrays feasible, nevertheless resulting in a slightly lower InGaAsSb material quality. GaSb has been also used as second substrate material candidate: indeed it is easier to grow high quality layers on GaSb even though the bandgap of GaSb prevents to use it in 2D focal planes.