Abstract: The present invention relates to an antenna which is electronically reconfigurable in transmission. The antenna comprises an array (11) of elementary sources, an energy-focusing reflector (10), with the array (11) being situated in the focal zone of the reflector, and control and feed electronics, the electronics comprising an amplifier stage (22) constituted by amplifiers (24) and including at least one generalized coupler disposed at the outputs of the amplifiers (24), and beam-forming circuits (20, 21) each corresponding to a transmitted beam, with the amplitude and relative phase of the signals leaving said circuits being controlled by respective adjustable phase shifters and adjustable attenuators. The invention is particularly applicable to space telecommunications.