The present invention relates to an amplification device for a satellite in order to amplify a plurality of n transmission channels to an output corresponding to a beam, the device comprising: frequency band combining means comprising n inputs in order to receive the n transmission channels and q outputs in order to supply respectively the channels grouped together within q frequency bands, a power amplification unit including p active amplifiers in parallel for the distributed amplification of the n channels, gain and phase adjustment means corresponding to the p power amplifiers on the q frequency bands.