15.6. Example 6
In this example, we are going to calculate the monostatic RCS of a custom chaff (Ellipsoidal parametric cloud) with a frequency sweep (5 samples from 8 GHz to 12 GHz) using MoM (Method of Moments).
Step 1
First, start newFASANT.
Step 2
Select “File → New” (or, alternatively, press Ctrl+N), and select Chaff from the list of modules by clicking in the following button:
Chaff module button
Step 3
Add a parameter to generate a parametric geometry. Select “Geometry→ Parameters→ Define Step” and enter the parameters as the next figure shows:
Parameters Definition
Step 4
Select “Geometry→ Solid → Ellipsoid”, and enter the same parameters as in the figure:
Ellipsoid command
Step 5
Select “Chaff→ Custom Cloud → Dipole”, and enter the same parameters as in the figure:
Custom Chaff → Dipole menu option
Chaff Parameters and Visualization
Step 6
Select “Simulation → Parameters”, select a frequency sweep from 8 GHz to 12 GHz with 5 samples as shown in the figure and press the “Save” button.
Simulation parameters
Step 7
Select “Solver → Parameters”, leave the default parameters and press the “Save” button.
Solver → Parameters Menu option
Solver parameters
Step 8
Select “RCS → Parameters”. Select “Monostatic RCS” with the default parameters.
RCS → Parameters Menu option
RCS parameters
Step 9
Select “Output → Observation Directions” and introduce the far field observations as in the next Figure. Press the “Save” button.
Output → Observation Directions Menu option
Far Field Observation Directions
Step 10
Select “Meshing → Create Mesh”.
Meshing → Create Mesh Menu option
Step 11
Select 10 divisions in both planar and curved surfaces and the default frequency value. One processor should be enough for the meshing process. Press the “Mesh” button.
Meshing parameters
Step 12
Select “Calculate → Execute”, choose the number of processor used to run the simulation and press the “Execute” button.
Selection of number of processors
Step 13
When the simulation has finished (i.e. the text in the progress bar in the bottom-right corner of the window is “Done.”) we can see the results. Select “Show Results → Far Field → View Cuts” to show the RCS graphic. The user can add more plots by selecting the desired frequency and pressing the “Add Series” button:
RCS graphic
Step 14
Select “Show Results → Far Field → View Cuts ByFrequency” to visualize the relationship of the RCS values and the frequency:
RCS-Frequency graphic
Step 15
Select “Show Results → Far Field → View Text Files”.
Show Results → Far Field → View Text Files menu option
Select one of the frequencies and press the “OK” button.
Far Field Text File panel
Visualizing results in text format
Selecting Monostatic RCS-Frequency files
Visualizing Monostatic RCS-Frequency text file