[Top] [All Lists]

[antennaware] Modelling Antennas over ground..

To: <>
Subject: [antennaware] Modelling Antennas over ground..
From: (Christoph Rheker)
Date: Thu, 16 Apr 1998 05:41:22 -0700
Has anyone some experience with modelling antennas over 
real ground, at low heigths?

For example:

I make a modell of a 20m Yagi in free space, resonant at 14,200 MHz.
It is a narrow band design. I let AO optimize the ant.

Now I put the ant over real ground at a low height, let's say at 5m
or 15 feet, 1/4 wave length.

Result: The pattern is changed because of the ground effects, as expected.
But I thought, the proximity of the elements to the ground will have a great
effect to the resonant freq of the elements and will make the ant misbehave.

Or in other words:
Is 1/4 wavelength high enough not to have any major influence on the
freq of the elements? Will modelling an ant at that low heigths give real

Chris DL4YAO

FAQ on WWW:     
Administrative requests:

<Prev in Thread] Current Thread [Next in Thread>