Define Radome by Material Surface

Define Radome by One Material Surface

Input or set the antenna. Set the surface of the internal face of the radome. The radome will be simulated by modelling this surface by a material surface.

Figure 1. Antenna and an internal surface of the radome layers.


If the material for modelling the radome is not available, add a new material for modelling the radome layers and FSS. This material considers the reflection/transmission coefficients. A file with these coefficients is obtained using PERIODICAL STRUCTURE (PS) module with a unit cell that models the radome layers/FSS , see Cell Menu and Training Examples.

Figure 2. Example of the unit cell for modelling a radome surface composed by a dielectric layer of 1.4 mm of thickness, of material epsilon 4.2 that has a relative permittivity of 4.2 and is covered by a perfect electrical conducting surface with a cross-slot. Unit cell dimensions: 10x10 mm. Cross dimensions: total arms lengths = 9.25mm; wide = 1.20 mm. The upper face of the unit cell (metal with cross slot) corresponds with the internal face of the radome layer.


Get and output the Rx/Tx matrices in the PS module.

Figure 3. Save the file with the Rx/Tx matrices obtained in the frequency range from 9.0 to 10.0 GHz with 0.1 GHz Steps.


Define in MOM module a material with the Rx/Tx matrices generated in PS module. This material must be saved for future simulations.

Figure 4. Assign the new material to the radome.


Select Use transmission coefficients and in the Thickness field, set the thickness of the unit cell.

Mesh and run the case.
Figure 5. Assign Material to the radome surface.


Define Radome by Several Material Surfaces

User has the option to split complex thick layers into two or more layers structures, in such a way that these structures together compose the original structure. Figure 6 shows an example of this splitting.
Figure 6. Example of the unit cell for modelling a radome surface composed, starting from the top by metal with cross slot, a dielectric layer of epsilon 4.2 and thickness 1.4 mm, a layer of foam (relative permittivity 1.05) of 3.6 mm of thickness, metal with cross slot and in the bottom a dielectric layer of epsilon 4.2 and thickness 1.4 mm. Notice that the total height of the unit cell is 6.4 mm. The surface at the top of the cell corresponds with the internal face of the radome.


Figure 7. The radome layers is split into two unit cells: Unit cell (a) in the left is composed by, starting from the top by metal with cross slot, a dielectric layer of epsilon 4.2 and thickness 1.4 mm and a layer of foam of 1.8 mm of thickness; Unit cell (b) in the right composed by a layer of foam of 1.8 mm of thickness, metal with cross slot and a dielectric layer of epsilon 4.2 and thickness 1.4 mm.


The radome structure is modeled by a set of material surfaces, each one of them corresponding to a structure resulting from the splitting. Figure 8 shows the case of the structure splitting of previous figures.
Figure 8. The radome is modeled by two material surfaces. The lower surface, of blue color has assigned a material that corresponds with unit cell (a) and the upper surface, of maroon color, corresponds with unit cell (b).


Figure 9 compares results for radiation pattern cuts with and without the splitting of the radome structure.
Figure 9. Radiation pattern cut, phi=0, at 9.5 GHz of the antenna with radome modeled by two material surfaces (red line), one material surface (blue line) and the antenna alone (green line).