Phil, K5PC wrote:
"I once sat in on a talk by Frank, W3LPL, that cleared up a lot of my
questions.
He correctly pointed out that not only is the earth's surface and the sea
surface uneven, but the ionosphere can also be equated to an "upside
down" ocean that is seldom level and even, but is constantly rolling like
waves into shore. It does not provide a level surface in which to bounce
off of like a billiard table, so there is scattering at the top AND
bottom of the bounce."
====================
I agree with Frank that the ionosphere is "wavy", but I disagree that
ionospheric scatter is due to *bounce* off of that "ocean's" ripples. RF
is not *bounced* off of the ionosphere, but rather travels *into* it and
is refracted back toward the Earth (an instance where the signal does
follow a "curved" path). An analogy is the way light is refracted by a
prism. There might occur a condition where the signal is bent 180
degrees and comes back toward the point of origin -- I dunno.
Ionospheric *scatter* is a technique requiring *huge* amounts of power.
Ditto for tropospheric scatter.
73, de Earl, K6SE
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