On the propagation of transients in waveguides

Transient propagation in a rectangular waveguide is examined, using elementary dispersion theory. Simple experiments are presented, which validate the theory and illustrate the concepts of group velocity, wave-front velocity, and wave precursors in a rectangular waveguide. The precursor phenomenon is isolated by examining the step response of the waveguide, using a time-domain reflectometer, showing that the wavefront velocity never exceeds the speed of light.<
>