Topband: Modeling verticals (fat, skinny, etc) on EZNEC

[Guy Olinger, K2AV]

"...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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