Note also that this “cosine pulse” distribution is very similar to the triangular distribution of the ESD, and is reminiscent of the sinusoidal variation of current in a standing wave. The magnitude a...Note also that this “cosine pulse” distribution is very similar to the triangular distribution of the ESD, and is reminiscent of the sinusoidal variation of current in a standing wave. The magnitude and polarization of the radiated field is similar to that of the electrically-short dipole (ESD; Section 9.5). Figure \PageIndex2: Comparison of the magnitude of the radiated field of the HWD to that of an electrically-short dipole also oriented along the z-axis.