All antennas consist of conductors which have current conducted to them
from sources and induced in them by coupling to fields from other
conductors or other parts of the same conductor. These currents create
fields. Ground plane antennas work exactly the same as all others. In
that way they're simple to understand.

Yes, you can view it this way or that, with various degrees of accuracy
and inaccuracy. The problem is that people begin to believe that the
alternate views are really what happens, rather than attempts at
simplifying and understanding things. Before you know it, you've got
mirrors, "ground" high above the Earth, impossible reflections, and
other dubious concepts which end up leading people farther and farther
from really understanding the basic principles involved.

Roy Lewallen, W7EL

David wrote:
One of the earlier postings suggested that the quarterwave vertical antenna
with radials was elementary and easy to understand. I have never found this
antenna easy to understand.

RF experts on this newsgroup cannot agree on whether i) the radials reflect
the wave or ii) the field from the radials cancels out. The standard
academic books show that the principle behind the vertical ground plane
antenna is that the vertical radiating element emits the wave, and is
reflected by the ground plane.

You can view a conductor as having current pushed through it by a RF source,
or the current can be induced in the conductor by the wave. This is a
boundary condition in Maxwell's equations, referred to in theory of
transmission lines and guided waves.

You can view the radials as reflecting the wave and having current induced
in them, or they can have current pushed through them by the RF source. This
is probably the same thing, due to the arrangement of all antenna parts
forming the antenna impedance. In image theory, the impedance comes from
both the self impedance and the mutual impedance.
. . .