HFSS boundary, wave port conditions for antenna with feed

Hello everybody,

I have an antenna with a feed-line where I have as an excitation a wave port. There are two possibilities to place the air box. You can create the wave port in the same plane as the radiation box or the box is λ/4 far away from the beginning of the feed line where a wave port is placed. So what is the simulation rule?

Re: HFSS boundary, wave port conditions for antenna with fee

Heikoo,
if u upload your file I could better understand ur problem and I can try to fix it.

I.

Re: HFSS boundary, wave port conditions for antenna with fee

Ok., I have added an file with the two possibilities.

Re: HFSS boundary, wave port conditions for antenna with fee

ok,

1st possibility: the wave port is inside the airbox. The simulation rule is to draw a very thin PEC brick and assign the port to the PEC brick face touching the antenna (looks to be fed with a cpw, isn't it?). PEC is a 'non-solve inside' material in HFSS. Waveports must be placed between a 'non-solve inside' (no meshed) and a 'solve inside' material (meshed like dielectrics, etc.). This solution is typically used when there's a special need to use waveports as so called 'internal ports';

2nd possibility: draw a rectangular sheet touching the airbox and assign the waveport. This is the most common way to use waveport, simpler to be drawn. I think this better suits ur needs, actually there's no need to put the waveport inside the airbox in ur case.

The two situations are, anyway, equivalent.

I.

Re: HFSS boundary, wave port conditions for antenna with fee

Thank you.
I am still working 2nd method.