In-orbit molecular contamination can rapidly degrade the performance of sensitive sub-systems, such as optical instruments, thermal control surfaces and solar arrays. In existing spacecraft design, most of the effort is concerned with reducing the contamination potential at source e.g. by limiting high outgassing materials, reducing view factors between materials and the surfaces etc. However this is generally a very complex task, and, despite best efforts, contamination in-orbit cannot be fully eliminated.

Currently EO missions are operated in S/X-Band with payload data in X-Band. New EO missions will have payload data in K-Band and TTC still in S-Band. In the long term TTC will be moved to X-Band still keeping payload data in K-Band. Presently only US suppliers are able to provide antenna radomes operating over different frequency bands. It is intended to develop an European alternative to US suppliers in the domain of high/multi-frequency application like the one needed for future Earth Observation missions.

Aluminium-based alloys obtained by a rapid solidification process have been successfully used for manufacturing optical mirrors. The maximum size of this type of aluminium mirrors is limited by the size of the billet, i.e. currently considered to be approximately 500 mm with and homogeneous microstructure. Consequently, the current manufacturing processes allow to produce mirrors with an effective area limited to a maximum dimension of 400 mm . The need for larger Aluminium-based mirrors is coming from scientific missions that require a large collecting area.

GNSS observations, as taken by global GNSS sensor networks, are affected by a multitude of effects impacting the quality of the GNSS observations itself as well as the derived products. This is especially true for high accuracy products like precise orbits and clocks and also for corrections applied for real time applications. The effects impacting the GNSS observations range from unexpected GNSS behaviour, atmospheric disturbances (e.g. scintillation), environmental (e.g. multipath, antenna, ?) and seasonal effects up to those which are depending on the GNSS receiver behaviour.

The Doherty concept has proven to be a very effective technique for designing amplifiers, which maintain a high efficiency over a wide range of operating conditions. This technique is extensively used in terrestrial applications like base stations where power efficiency is getting more and more attention. Power efficiency is also of concern for space and the Doherty concept could certainly help in designing more efficient PAs. Ka-band is now being considered for mobile services that could offer very high capacity as compared to the existing ones at L-band.

Accurate localisation of assets on planetary bodies will be crucial in future exploration missions when it comes to autonomous vehicles navigation and accurate positioning. On Earth, dedicated systems in L-band are typically used for navigation and localisation.