Active rectifier with modulation

The present document relates to isolated electrical systems coupled e.g. by a transformer / inductor system, a piezo transformer, a capacitor or other isolation means. In particular, the present document relates to a method and system for communicating across isolation means in isolated electrical systems. A rectification circuit (500) configured to generate a direct current at an output of the rectification circuit (500) subject to an alternating voltage at an input of the rectification circuit (500) is described. The rectification circuit (500) comprises coupling means (506) at the input, configured to receive the alternating voltage from a galvanically decoupled electronic subsystem; a first switch (514) arranged between the coupling means (506) and the output, configured to block current in a first direction and to conduct current in a second direction, opposite to the first direction, thereby contributing to the direct current; wherein a resistance of the first switch (514), when conducting current in the second direction, is adjustable; and a first modulation unit (520) configured to receive encoded information; map the encoded information to a first modulation state from a plurality of different modulation states of the resistance of the first switch (514); wherein each of the plurality of modulation states specifies a resistance value and/or a temporal evolution of the resistance value of the resistance of the first switch (514); and adjust the resistance of the first switch (514) according to the first modulation state, thereby modulating the current conducted by the first switch (514) according to the first modulation state.