Hi although I can visualize a transmitted 'wave angle' as the elevation of peak
field strength, and its relative strength at other angles forming a "lobe" -
what is the situation for sky wave signals as they are received at a far point
after being refracted by the ionosphere? When we speak of an arrival angle - is
that the discreet angle perpendicular to the arriving plane wave or is that the
angle at which a theoretical elevation sampling antenna would receive the
highest strength signal? Maybe they are one and the same. What I am trying to
visualize though is the angular "width" of the arriving signal. When HFTA says
a path will open at a 9 degree wave angle does anyone have any idea how the
propagated signal strength falls off at other angles? I imagine both the peak
angle and range of angles being propagated varies from moment to moment for a
given frequency and path as the ionosphere shimmers but wonder if anyone has
seen data about this question.
_________________
Topband Reflector
|