Reply To: Simulating Backscatter From Dielectric Surrounded By Metal

[Faezeh Ladani]

Hi Lucio, 

What is the solution frequency? Note that SBR+ is suitable for objects which are electrically large. Also, if the coating is thicker than skin depth, then no field is going to penetrate inside the glass and there is no need to solve for that. If this is a case where coating is thinner than skin depth, then likely the case is at low frequency and not appropritae for SBR+ regarding electrical size. You can use FEM and define the coating as shell element finite conductivity boundary. 

If it is the case where you need to model it in SBR+ and also consider the field penetration through the coating, then assign layered impedance boundary on the surface of glass sphere and assign respective coating material and thickness. You can also use Fresnel boundary condition in SBR+ which accounts for power reflection and transmission through the layer. You can look Fresnel_BC_SBR+ example in HFSS Open Examples.

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