On Jun 7, 5:00*pm, Cecil Moore wrote:
On Jun 6, 1:01*pm, K1TTT wrote:

as in the other thread, what is the mechanism of that 'interaction'
between waves? *i contend there can be no 'interaction' between
forward and reflected waves if the device is linear.

David, you are preaching to the choir. I explained before that there
is NO interaction between forward and reflected waves because they are
traveling in different directions. The only time that coherent,
collimated waves can interact is when they are traveling in the same
direction in a transmission line.

Keith's argument requires that forward waves and reflected waves
interact. I say they cannot interact in a constant Z0 environment. You
say they cannot interact. We are on the same side of this argument.

The mechanism of the interaction of two coherent, collimated waves
traveling in the same direction is that the superposition process is
irreversible. The source photons and the reflected photons are
indistinguishable.
--
73, Cecil, w5dxp.com

This is what YOU said:

What happens to the 50 joules/second of reflected energy depends upon
the phasing between the source wave and the reflected wave at the
source impedance. What most amateurs don't understand is there are
two mechanisms that can redistribute reflected energy back toward the
antenna. Those mechanisms are a re-reflection based on the physical
reflection coefficient (what RF engineers understand) and wave
interaction resulting in constructive/destructive interference (what
most RF engineers don't seem to understand) because, unlike optical
physicists, have not been forced to follow the energy flow.

There is no interaction between the waves, they may be superimposed,
and maybe their photons are indistinguishable, but there is no
'interaction'. interaction implies that one wave affects the other,
energy is transferred or fields are affected, such things occur in non-
linear media, but not in linear ones.

On Jun 7, 4:21*pm, K1TTT wrote:
There is no interaction between the waves, they may be superimposed,
and maybe their photons are indistinguishable, but there is no
'interaction'. *interaction implies that one wave affects the other,
energy is transferred or fields are affected, such things occur in non-
linear media, but not in linear ones.

Note that I was not talking about forward and reflected waves in a
constant Z0 transmission line. I am talking about the four wavefront
components that are generated at an impedance discontinuity. It has
been proven in experimentally that those waves indeed interact. In
fact, the transfer of destructive interference energy from wave
cancellation to the areas that permit constructive interference is
obviously interaction since the canceled waves disappear in their
original direction of travel. But, as the FSU web page says, they are
not annihilated - their energy components simply change direction.

How can you possibly argue that wave cancellation doesn't require wave
interaction? Those two waves completely disappear in the direction of
destructive interference. Dr. Best argued that those two waves don't
interact and continue propagating (completely devoid of energy)
forever in the direction of original travel. I asked him to prove that
his phantom waves exist but he could not. Is there such a proof
available?

At a 1/4WL thin-film coating on non-reflective glass, when the
internal reflected wave arrives with equal magnitude and 180 degrees
out of phase with the external reflection, wave cancellation occurs.
That is an *obvious* effect that one wave has on the other. Wave
cancellation is an obvious interaction. In the s-parameter equation:

b1 = s11*a1 + s12*a2 = 0

the s11*a1 wavefront has obviously interacted with the s12*a2
wavefront to accomplish wave cancellation.
--
73, Cecil, w5dxp.com