How can I get closely matched impedance results for Infinite Ground Plane vs. Finite Ground Plane for Patch Antenna?

Lucas_22461

Hello,

Apologies if this has been asked, but I could not find a specific forum post about this.  How do I get my infinite ground plane results to match fairly closely to finite ground results for a simple microstrip antenna?  Attached is a FEKO model for the infinite ground plane version.  Am I setting this model up correctly with a wire port?  If so, how would I translate that to a finite ground version with finite substrate, in this case Megtron?

Edit:  I should mention that, I have been modeling this antenna for quite some time and just recently found that the infinite and finite ground planes' impedance/reflection vary by a few dB in the 77-81GHz range.  The gain patterns vary also, but that is manageable and makes sense.  

Thank you for your help,

Lucas

Transmit and Receive Arrays _SingleElement_ConnectPorttoInfiniteGround.cfx

Jaehoon

Hello, Lucas

I'd like to share some simulation comparison data for your structure.)

(I included only your antenna part which is the most important.)

 

I used four different solvers in Feko as shown below.

 

 

 

As you can see above, this is not a matter of infinite or finite structure. 

You might check more with the attached files which I simulated.

(There is no difference if the finite area is big enough.)

 

Of course, the far-field patterns show some difference between infinite and finite structures.

 

Thank you.

Jaehoon

Comp.zip