[Antennas] Modeling yagi
Harvey&Bessie
[email protected]
2002年3月16日 20:55:06 -0500
The "ground" directly under a horizontal antenna has very little effect
upon the propagated wave at a distance for low radiation angles in the
far field. For modeling purposes we must consider the ground at the
reflecting point, not that lying directly under the supporting
structure, except for the higher radiation angles. For the case you
postulate, this makes reliance upon modeling programs very "iffy."
In other words, for low radiation angles, the earth some distance from
the building would determine the height above ground, whereas for higher
radiation angles, the height above the roof would be taken as the height
above ground.
Harvey/W4TG