How to fix the error in this infinite ground plane coaxial probe -fed patch design ? v2023.1 FEKO

sswh2

coax_probe_infinite_ground.cfx

Hello,I am getting a simulation error for the infinite ground plane coaxial probe-fed patch antenna design. The error message indicates that the coaxial outer layer is intersecting with the coaxial probe. Could anybody help me fix this error so I can run this model?

mvogel

One thing I notice is that the object Outer has been placed a bit too low. The top is below the substrate (leaving a gap) and the bottom is below the inner conductor (so the inner conductor doesn't touch the port anymore).

I recommend you fix that first. I should mention that I opened it in a newer version than the one you have.

For the infinite layers, you probably want this:

This gives free space above and below, with one substrate which has a ground plane. In this setup, the ground plane does not have a thickness anymore.

For Outer, you may want this:

Then still, I keep running into Feko limitations related to the infinite layers. Maybe you'd be better of with a finite substrate, even if that is computationally more expensive.

mvogel

With_Edge_Port_Before_Union.cfx

With_Edge_Port_After_Union.cfx

You are right, it turns out that the dielectric of the coax cable has to stay away from the ground plane. Once I had gotten past that hurdle, Feko told me that wave ports and infinite layers cannot be combined. Sigh. I have attached two version 2022.3 projects (you should be able to open them in your version of Feko). The projects bypass the hurdles, leaving a space between the coax dielectric and the infinite layers, and replacing the wave port by a lumped port.

Note the property of the face that forms the hole in the ground plane:

mvogel

One thing I notice is that the object Outer has been placed a bit too low. The top is below the substrate (leaving a gap) and the bottom is below the inner conductor (so the inner conductor doesn't touch the port anymore).

I recommend you fix that first. I should mention that I opened it in a newer version than the one you have.

For the infinite layers, you probably want this:

This gives free space above and below, with one substrate which has a ground plane. In this setup, the ground plane does not have a thickness anymore.

For Outer, you may want this:

Then still, I keep running into Feko limitations related to the infinite layers. Maybe you'd be better of with a finite substrate, even if that is computationally more expensive.

sswh2

@mvogel thank you for the explanation! but if I don't keep the outer cable slightly bellow I am getting error thats why I placed slightly bellow the ground plane. I need infinite ground for my model, can you kindly fix my attached model and upload here? I am still getting error.

mvogel

With_Edge_Port_Before_Union.cfx

With_Edge_Port_After_Union.cfx

You are right, it turns out that the dielectric of the coax cable has to stay away from the ground plane. Once I had gotten past that hurdle, Feko told me that wave ports and infinite layers cannot be combined. Sigh. I have attached two version 2022.3 projects (you should be able to open them in your version of Feko). The projects bypass the hurdles, leaving a space between the coax dielectric and the infinite layers, and replacing the wave port by a lumped port.

Note the property of the face that forms the hole in the ground plane:

sswh2

@mvogel Thank you so much!