Simulation of antenna in ANSYS HFSS

[AmateurRadist 6]

Hi everyone, here i simulated  5.8GHz panel antenna in HFSS 2020R2, some results not showing correctly, what might be the problem?  

58ghz_panel.aedt

[Admin 2578]

Ground Plain is missing

[Docgi 4]

It looks like there is a ground plane but you made it transparent. If it's possible, would you like to share the aedt file with me. I can examine the whole design for you and maybe optimize it. 

[AmateurRadist 6]

25 minutes ago, Docgi said:

It looks like there is a ground plane but you made it transparent. If it's possible, would you like to share the aedt file with me. I can examine the whole design for you and maybe optimize it. 

aedt file link is under the photo

[AmateurRadist 6]

@Admin I created GP and validation was ok,  maybe somehow saved incorrectly or i don't know

[Admin 2578]

Then the mistake is somewhere else(on 3D Model)...!!!

[Docgi 4]

 @Admin @AmateurRadist There is ground plane in the design but I realized that you selected "Display Wiframe" option on material properties. If you unclick it you can see ground plane easily

[Docgi 4]

This is also the warning you get, because you also choose solve material inside for conductive material. I don't recomend that option for conductive materials, unless you want to look the Skin effect. If you unclick it the warning is gone

Edited December 15 by Docgi

[AmateurRadist 6]

@Docgi thanks,  so i was getting some errors and i googled it and to solve it i had to click on "solve inside", it seems this created another error   

[Docgi 4]

@AmateurRadist I simulated you design and then made some changes. First there are many mistakes I beleive you need to fix and I'll show you some. I did another simulation for wider bandwidth to see antenna performance. Looks like there is lots of optimization to do because if you look at the results antenna has minimum return loss at higher frequencies but max realized gain at lower frequencies. So the whole design should be optimized I guess.

[AmateurRadist 6]

@Docgi thank you very much for detailed answer,  actually cylinders were plastic spacers, so i didn't assign any material, after your suggestion i deleted them.  Now it looks far better, i'm wondering why half radiation goes backward eventhough there is ground plate,

and how you check S11 parameter? in my "far field report" section there is no S11

Also vswr is very high, how i can lower it?

thanks in advance

58ghz_new.aedt

[Docgi 4]

1 hour ago, AmateurRadist said:

@Docgi thank you very much for detailed answer,  actually cylinders were plastic spacers, so i didn't assign any material, after your suggestion i deleted them.  Now it looks far better, i'm wondering why half radiation goes backward eventhough there is ground plate,

and how you check S11 parameter? in my "far field report" section there is no S11

Also vswr is very high, how i can lower it?

thanks in advance

58ghz_new.aedt

@AmateurRadist If you look at the first picture you send "ground" is look unassigned so there is no reflecting plane in that simulation, assign PEC boundry. 

Also as you said your design file didn't have S11 plot so I put it myself when I simulate it. 

To lower VSWR I think you should focus on feeding line and patch sizes. Maybe you could cut feeding point of patches like in below picture. But I think feelind line is more important in your design

Edited Sunday at 06:43 PM by Docgi

[AmateurRadist 6]

10 hours ago, Docgi said:

you send "ground" is look unassigned so there is no reflecting plane in that simulation, assign PEC boundry. 

i didn't noticed that, now it looks far better with your hints, 

regarding S11 parameter, in data report section there is no such, so is it calculated in HFSS with a formula? like s11 = gamma = (Z-Zo)/(Z+Zo) 

[dumser2 18]

15 hours ago, Docgi said:

@AmateurRadist If you look at the first picture you send "ground" is look unassigned so there is no reflecting plane in that simulation, assign PEC boundry. 

Also as you said your design file didn't have S11 plot so I put it myself when I simulate it. 

To lower VSWR I think you should focus on feeding line and patch sizes. Maybe you could cut feeding point of patches like in below picture. But I think feelind line is more important in your design