Horizontally polarised antennas.
If the antenna above the ground plane is horizontally polarized:
, since the horizontal component of the electric field must
vanish on the conducting ground plane. The radiation pattern is appropriate to elements spaced
2h and fed in antiphase. The fields are zero on the ground plane however far from the sources.
There are lobes in the vertical plane, which narrow and increase in number as
the height h increases. However, the lobe maximum closest to the ground is at an angle to the
horizontal, the differential phase delay between the radiation from the source and the image
amounts to one half wavelength. We expect the field strength in this direction again to decrease
as 1/distance, and the radiated power density to decrease as 1/(distance^2).
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