A device and method are disclosed for synthesizing a waveform having pulse
segments. An exemplary generator can include units having a time delay
element and pulse generator generating the pulse segments. An input
divider divides an input signal into signal instances that propagate
through the units and an output combiner combines pulse segments to form
the waveform. The pulse generators include a sharpening circuit for
sharpening a rising edge and a falling edge of the pulse segments. The
sharpening circuit includes a tunable delay element coupled to a
non-linear transmission line (NLTL). Another NLTL can be coupled in
parallel with the tunable delay element and the first NLTL. The NLTLs
include input sections coupled to anodes or cathodes of Schottky diode
elements, and the respective cathodes or anodes are coupled to a signal
ground.