A device (D) is dedicated to transmitting and/or receiving signals representative of data in a communication satellite (SAT) having a fixed frequency bandwidth. This device (D) comprises transmission and/or reception means (MER) responsible for sending and/or receiving signals in multiple beams, and control means (MC) responsible for defining a chosen number of cells of chosen dimensions and positions, and configuring the transmission and/or reception means (MER) so as to define beams each associated with at least one of the defined cells, with a chosen carrier frequency based on the requirements of each of the cells and taking into account the frequency bandwidth available on the satellite (SAT).