Methods and devices for generating, from a DC voltage, a periodic voltage of sinusoidal shape which can be amplitude-modulated

摘要

The subjects of the invention are methods and devices for generating, from a DC voltage, a staircase voltage of sinusoidal shape and for modulating the amplitude of the latter. A device according to the invention includes a stepped synthesiser which includes a plurality of stages each composed of an H-shaped bridge switch (51, 52,...5n) and of a transformer (61, 62,... 6n) and the secondaries of all the transformers are connected in series with a load 3 by way of an amplifier and impedance matcher circuit 4. The transformation ratios of some of the transformers follow a geometrical progression of ratio three. One application is the excitation of a transmitter antenna of a power sonar. <IMAGE>