Richard Harrison wrote:
If a directional
coupler is used to measure the current in each direction separately, it
will be found that the currents traveling in opposite directions are
passing through each other without effect. Standing waves are more
manifestation than anything else.

And this is equally true of standing wave antennas. Kraus goes
as far as assuming the forward and reflected currents on a
1/2 wavelength thin-wire dipole are equal in magnitude so
they must be close to equal in magnitude. I have estimated that
the magnitude of the reflected current after the round trip
to the end of the dipole and back to be in the ballpark of
90% of the forward current at the feedpoint.

This entire episode of constant current through a loading coil
is the result of thinking standing wave current flows. As you
say it is a manifestation of our thinking process and our
measurements. It doesn't flow at all.

Incidentally, a horizontal dipole above earth can be analyzed
as a single-wire transmission line system with the earth being
the ground return path. Balanis says, "Standing wave antennas,
such as the dipole, can be analyzed as traveling wave antennas
with waves propagating in opposite directions (forwards and
backwards) and represented by traveling wave currents If and Ib
in Figure 10.1(a)."

The forward current (If) through a loading coil is very close
to constant magnitude. The reflected current (Ib) back through
a loading coil is very close to constant magnitude. Their
phasor sum is the standing wave current that we measure. There
is no physics requirement that the phasor sum of the forward
and reflected currents be of equal magnitude on both ends of
the loading coil.
--
73, Cecil http://www.qsl.net/w5dxp