Several SAR future Earth Observation missions requires large reflector antennas generating highly directive overlapped beams. This has been done so far with high power waveguide Beam Forming Networks including ferrite switches as implemented for Core H2O pre-developments. In this activity, it is proposed to investigate reflector antennas fed by overlapped subarrays. This represents an extremely promising concept for on-board SAR instruments.

Passive intermodulation is a real threat to all types of payloads. In some cases, it could even lead to total lost of the spaceship. Despite of this, there is very weak understanding of the parameters that generate this unwanted interference as well as their influence in the amplitude of the interfering signal. In addition, there is a total lack of agreed testing techniques, procedures and methodologies as well as justified test margins, as has already been recently stated by the European community (National Delegations, satellite operators and Eurospace).

The interest of having in the near future an available Position, Navigation and Timing (PNT) service supporting future missions to and at the Moon is currently supported by both institutional and commercial initiatives. On the commercial side, multiple companies are developing business solutions targeting the Moon and several major European companies are proposing to team up to build a communications network on the Moon compatible to terrestrial standards. In parallel, NASA has recently announced its plans to a ?Return to the moon?

The use of higher frequencies is becoming necessary for supporting feeder links of High Throughput Telecom Satellites due to the larger bandwidths available. Q and V bands are now being considered as a baseline for next generation systems. The next step will be to look at W band. In order to understand the system sizing, it is necessary to have a good modelling of the propagation channel. So far no measurement campaign has been done, therefore it is needed to start characterizing the channel.

Despite different attempts performed in the past two decades, Europe is lacking a competitive product for a large reflector with the requested TRL level to embark on a commercial program. Need is identified to cover antenna applications from 4 up to 18 meter and for frequencies from UHF up to Ka band.. American companies are leaders in this domain and are commercially dominating the worldwide market.

The authentication of GNSS signals poses a challenging problem. Before exploiting a signal (e.g. its pseudo-noise sequence) it would be desirable for the receiver to have assurance quickly (ideally in less than 10-s) and reliably that the signal is actually coming from a navigation satellite and not from a spoofer (e.g. unknown pseudolite, delayed version of the same signal). Classical data-level authentication solutions work after signal demodulation (PN sequence de-spreading), require data-level cryptography (shared secrets) and key management.

High-sensitivity GNSS receivers architectures are of interest in harsh propagation conditions in order to be able to keep tracking GNSS signals even at very low C/No conditions (typically down to around 10-20 dBHz, depending on the signal being tracked). For this purpose, open-loop techniques can be used in the estimation of the code delay and the carrier phase and/or frequency, targeting a more robust estimation of those observables. In this process, advanced signal estimation techniques can be applied for the optimum exploitation of e.g. multi-correlation samples.