The high voltage aspect of most pulsed power circuits imposes generally quite large
dimensions and spacings on circuit elements in order to achieve workable electric
stress levels. When electrical energy is required to be delivered in the form of short
pulses, the physical separation between circuit elements often makes it necessary for
these pulses to be delivered along some form of transmission line. The transmission
lines will be two-conductor lines e.g. coaxial or parallel-plate, supporting TEMmode
waveforms as the principal mode. Helical slow wave lines are also used. The
transmission line transmits power according to the telegraphers’ wave equations. It
can support forward and backward travelling waves.