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Old August 14th 07, 10:37 AM posted to rec.radio.amateur.antenna
Wimpie Wimpie is offline
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First recorded activity by RadioBanter: Aug 2006
Posts: 106
Default Can A Patch Ant. be modeled in EZNEC?

On 14 ago, 02:11, "amdx" wrote:
Can a Patch Antenna be modeled in EZNEC?
Do you make the flat plates with parrallel lines?
Or is there a function to give you a solid plate?
Mike


Hello Mike,

As Jim wrote, Patch Antennas are tough with wire-based codes.

In NEC you are limited to Patch Antennas without a dielectric layer,
so deformation of the radiation pattern because of radiation from the
dielectric will not be shown.

I assume that you start with simulating above a perfect ground. In
that case start with grid size of about half the distance between
ground and your patch. Use a grid instead of parallel wires. Parallel
wires do behave different from a grid when you may expect current
flowing perpendicular to the wires (for example close to the feed
point).

Use a wire radius of about 20% of the grid size. This results in a
wire radius of 10% of the distance between grid and ground. Run your
simulations with varying grid size to evaluate the effect of grid size
on accuracy.

You may have a look at sonnet lite (www.sonnetusa.com) when you are
interested in input impedance and matching only. With sonnet lite you
cannot get radiation patterns as far as I know.


I hope this will help you a bit.

Best regards,

Wim
PA3DJS
www.tetech.nl