Current X-band links from LEO satellites to ground stations are limited in data rates because of their low gain, due to the global coverage by a single beam. In order to increase the data rate while keeping low DC consumption (so low transmitted power) and to enable simultaneous links with several ground stations, a multibeam scanning antenna was designed and a demonstrator (up to three beams in three adjacent sub-bands) manufactured for an observation mission at an altitude around 800 km. A conformal array was selected by Alcatel, in agreement with ESA, as the best option for such a mission, because of its higher gain compared to a passive fixed beam and its capability of electronic scanning which avoids any mechanical disturbances.