"...I think we are having a semantic issue here." As if to diminish
Tom's correct argument by labeling it?
Attention to careful language that does not lend itself to false
mental simplifications is important for the sake of anyone trying to
learn something new.
Horizontal polarization and vertical polarization are NOT two natural
modes. They are merely convenient descriptive methods for us because
we live on the surface of a planet, because antennas fall into
predictable orientations related to that surface, and because
radiation with polarization perpendicular to the earth's surface can
behave differently than parallel when striking that surface. This last
is an electrical characteristic of the surface, not a "mode" of
polarization.
Take a receiving and transmitting dipole into space. Or, lacking
transportation, model in free space.
When the receiving and transmitting dipole are parallel, and the line
between their centers is perpendicular to the dipoles, the maximum
energy transfer for their distance will take place. Assuming they are
at least a few wavelengths apart, rotate one dipole in any fashion
away from that orientation and the energy transfer diminishes.
What has happened is that dipole A polarization is no longer the same
as dipole B's polarization. Further, it is seen that linear
polarization is three dimensional. Said another way, the calculation
of transferred energy in free space cannot be calculated without
knowing (in addition to distance) the roll, pitch and yaw of both
dipoles from some common reference.
And, if one is out in space, just exactly what IS horizontal and
vertical, anyway, except a relationship to a completely arbitrary
plane of reference, no more naturally defined than "up" or "down".
73, Guy.
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