Objective:The objective of the activity is to develop and test a scalable, generic and reconfigurable multibeam transmit antenna architecture for feeder links operating in Q-band and supporting high-capacity geostationary broadband multimedia missions.TargetedImprovements:- Replacement of multiple (typically two or more) feeder link reflector antennas by a single antenna.- System deployment before finalisation of the gateway locations (6-12 months reduction of system deployment time).- Enabling modification of the positions and power of the beams towards the gateways.Description:Q/V band is already used for the feeder link on board Very HighThroughput Satellites (VHTS) in the geostationary Earth orbit using reflector antennas. One of the challenges of this approach is that the location of the gateways is often not known at the time of the satellite launch and gateways may be added during the satellite lifetime. Accordingly, there is a drive to employ reconfigurable active feeder link antennas.This activity will develop and experimentally test a scalable, generic and reconfigurable multibeam transmit antenna architecture for feeder links operating in Q-band.Trade-offs, including direct radiating array and array fed antenna architectures, will be carried out and a baseline developed. Radiating elements, beamforming networks, active elements and a thermal management system will be traded-off in the design. For the active elements, priority will be given to European technology. The active antenna shall be able to generate steerable beams in dual polarisation that can be pointed to any location within the Earth field of view. Different beamforming and antenna configurations thatallow flexible power distribution shall be considered and traded-off. A RF, mechanically and thermally representative scaled breadboard with critical functions of the active transmit antenna shall be designed, manufactured and experimentally tested. At least two reconfigurable feeder link beams associated with two different gateways shall be experimentally demonstrated.