Abstract: Device and process for the generation of amplitude-modulated radiofrequency excitation pulses. A first unit (2) delivers a radiofrequency signal of constant level and a second unit (3) delivers a modulation signal of the radiofrequency signal, formed from numerical data. At least two analog multipliers (6) are connected in cascade as to the radiofrequency signal (RF) from the first unit (2) and are supplied in parallel by the modulation signal (SM) from the second unit (3). For n multipliers (6) in cascade, with n.gtoreq.2, the modulation signal (SM) delivered to the n multipliers (6) is of the A.sup.1/n.f(t) type, A.f(t) being the desired resulting modulation signal (SMR). The second unit (3) is a memory (4) containing point by point the envelope of the modulation signal A.sup.1/n.f(t) and a digital/analog converter (5) whose output is connected to the inputs in parallel of the n analog multipliers (6) in cascade.