I use IE3D to do my patch simulation.
Recently I did a test where I simulated a simple
patch antenna (it was at about 1GHz) and looked
at the 3D radiation pattern, I saw that the pattern
is ending at the XY plane where the field is ZERO,
than I changed the first layer so it won't be a
metal strip and drew a new ground plane, the simulation
result where almost the same. and now for the surprise:
I added a thick layer of air under the ground plane
(hoping it will help me get a pattern at the negative
Z direction) and what I got is a better Gain result!
(over 1 dB better) and still no radiation to the
Can anyone help me understand
why? why the results were better with a thick air
layer under the ground, and more important why or
how I can get a radiation resault in the -Z direction.
(for port I used the "probe to patch" option
with the ground plane as negative and the patch
as the positive).