The example is intended for users with no or little experience with CADFEKO. It makes use of a completed rectangular horn model to familiarise yourself with model creation in CADFEKO and viewing the simulated results in POSTFEKO.
The example is intended for users with no or little experience with CADFEKO. This example is not an example intended for simulation, but rather to familiarise yourself with model creation in
CADFEKO.
Calculate the input reflection coefficient and circular components of a left-handed circular polarised GPS patch antenna
on a finite substrate close to 1.57 GHz.
Use macro recording to record actions in a script. Play the script back to automate the process or view the script to learn
the Lua-based scripting language by example. Macro recording allows you to perform repetitive actions faster and with less effort.
Define a lossy frequency-independent dielectric with a relative permittivity () = 5.6 and a dielectric loss tangent () = 0.0041 to be used as the patch substrate.
Union the geometry (feed_line, patch and substrate) to create a single geometry part. A single geometry part will ensure mesh connectivity when the model is meshed.
Voltage sources and discrete loads are applied to ports and not directly to the model geometry or mesh. A port must
be defined before a source or load can be added.
Specify the frequency range of interest. For this example continuous frequency sampling is used where Feko automatically determines the frequency sampling for optimal interpolation.
When the frequency is set or local mesh settings are applied to the geometry, the automatic mesh algorithm calculates
and creates the mesh automatically while the GUI is active using default mesh settings. When required, these mesh
settings may be modified.
Launch the Solver to calculate the results. No requests were added to this model since impedance and current information are calculated
automatically for all voltage and current sources in the model.
Feko is a comprehensive electromagnetic solver with multiple solution methods that is used for electromagnetic field analyses
involving 3D objects of arbitrary shapes.
EDITFEKO is used to construct advanced models (both the geometry and solution requirements) using a high-level scripting language
which includes loops and conditional statements.
One of the key features in Feko is that it includes a broad set of unique and hybridised solution methods. Effective use of Feko features requires an understanding of the available methods.
Feko offers state-of-the-art optimisation engines based on generic algorithm (GA) and other methods, which can be used
to automatically optimise the design and determine the optimum solution.
Feko writes all the results to an ASCII output file .out as well as a binary output file .bof for usage by POSTFEKO. Use the .out file to obtain additional information about the solution.
CADFEKO and POSTFEKO have a powerful, fast, lightweight scripting language integrated into the application allowing you to create
models, get hold of simulation results and model configuration information as well as manipulation of data and automate
repetitive tasks.
Change the surface property of the patch to perfect electric conductor
(PEC).
Change the face of the patch to PEC.
In the 3D view, left-click on the patch face
repeatedly until the face is highlighted in yellow.
Figure 1. Top view of patch and substrate. The yellow highlighting
indicates that the patch face is selected.
From the right-click context menu, select
Properties.
On the Modify Face dialog
(Properties tab), set the
Medium to Perfect electric
conductor.
Figure 2. The Modify Face dialog.
Click OK to change the face property and
to close the dialog.
Figure 3. Top view showing the face of the patch set to PEC.
Change the face of the bottom substrate to PEC.
In the model tree, under
Union1, select
substrate.
In the details tree, under
Faces, go through the list of faces. For each
face, click on to hide the face until only the bottom face of
the substrate remains.
Figure 4. Hidden items are greyed out when hidden in the 3D view.
From the right-click context menu, select
Properties.
On the Modify Face dialog
(Properties tab), set
Medium to Perfect electric
conductor.
Click OK to modify the face property and
to close the dialog.
Figure 5. Bottom view showing the bottom substrate face set to
PEC.
In the details tree, click on any of the faces.
From the right-click context menu, click
Show All to make faces visible again.
Note: The icon in the details tree indicate faces
set to PEC.