X-band reflect Array antenna

[Amra]

Hello everyone!
I am working on X-band reflect Array antenna and making the copy of a design from a research paper on HFSS. basically my design has an outer circular ring and in it is an I-shaped dipole. I've made the radiation box which is lamba/4 above the substrate and the lambda i used is of lowest frequency in the band 9.5GHz-11.5GHz.the solution frequency is 10.5GHz. I have used one floquet port on the top of radiation box and Master/slave boundaries. max no of passes are 6 and max delta s is 0.02. now when i analyze my design it says "Adaptive passes did not converge on specified criteria" and moreover the results are too much change from the results of research paper. I've tried many things changed the length of radiation box by taking the lambda of solution frequency in lambda/4, increased the no of passes up to 15, redesigned my whole design but nothing worked.:sad: .i really need to get the desired results in a day or two. please help me finding the problem. I shall be grateful.
I have attached both the research paper and my hfss design

 

[PlanarMetamaterials]

Hi Amra,

I don't know much about reflectarrays, but I do work with HFSS. Have you set up a seed mesh?

 

[Amra]

Hi Amra,

I don't know much about reflectarrays, but I do work with HFSS. Have you set up a seed mesh?

Infact I am also new to reflectarrays started working on it recently .... so will you please explain me what you mean by seed mesh?
If I am not wrong we use it instead of radiation box?
I've attatched my design too you can have a look and tell me if there is something I am missing... will be thankful

 

[PlanarMetamaterials]

Hi Amra,

A seed mesh is a starting mesh that you specify so that HFSS will spend less time "guessing" about how to construct the appropriate mesh, and converge more quickly.

You can set this up by right clicking an object and selecting "Assign Mesh Operation" -> "Inside Selection". A good rule of thumb I use is to assign a distance that is half of the minimum dimension of the object. I usually assign these seed meshes to the vacuum regions in between the metal traces.

 

[Amra]

Hi Amra,

A seed mesh is a starting mesh that you specify so that HFSS will spend less time "guessing" about how to construct the appropriate mesh, and converge more quickly.

You can set this up by right clicking an object and selecting "Assign Mesh Operation" -> "Inside Selection". A good rule of thumb I use is to assign a distance that is half of the minimum dimension of the object. I usually assign these seed meshes to the vacuum regions in between the metal traces.

I have my antenna of material copper on a substrate of duroid and below is ground plane of copper and this structure is surrounded by radiation box so where should I assign seed mesh?
On which object?
(Sorry if I am asking too much im new to it...)
Thankyou

 

[PlanarMetamaterials]

No problem,

I assume your reflectarray unit-cells are in the lower copper region - when you create the unit-cells make sure to leave (or add in) the vacuum around the copper segments, then mesh those.