Example 6: Common Simulation with a Coaxial Feed Source

This case explains how to calculate far-field, radiation pattern, current density, charge density, near field and impedance of an open box with a coaxial feed simple blade insides the box.

Step 1: Create a new MOM Project.

Open newFASANT and select 'File --> New' option.

Figure 1. New Project panel


Select 'MOM' option on the previous figure and start to configure the project.

Step 2: Create the geometry model. To obtain more information about geometries generation see Parameters.

Execute 'box' command writing it on the command line and sets the parameters as the next figure shows when command line ask for it.

Figure 2. Box parameters


Select box geometry on main panel and execute 'explode' command writing it on the command line. Then the box will be transformed into 6 surfaces.

Figure 3. Box selection and 'explode' command


Select the top surface and execute 'delete' command. Then the surface will be removed from the geometry.

Figure 4. Surface selection and 'delete' command


Select all remaining surfaces and execute 'group' command.

Figure 5. Surfaces selection and 'group' command


Step 3: Set Simulation Parameters

Select 'Simulation --> Parameters' option on the menu bar and the following panel appears. Set the parameters as the next figure shows and save it.

Figure 6. Simulation Parameters panel


Step 4: Set the source parameters. To obtain more information about sources and antennas see Antennas.

Select 'Source --> Primitive Antenna --> Coaxial Feed --> Blade --> Simple Blade' option and set the parameters as show the next figure. Then save the parameters and the antenna appears.

Figure 7. Simple Blade Antenna panel


Step 5: Set Near Field parameters.

Select 'Output --> Observation Points' option. The following panel will appear.

Figure 8. Observation Points panel


To add a line visualization, select 'line' on the selector of 'Geometry Types' section and click on 'Add' button. The line parameters panel will appear, then configure the values as the next figure show and accept it clicking on 'OK' button.

Figure 9. Observation Line panel


The observation line will appear as a dashed line on the position configured.

Figure 10. Observation Line visualization


Step 6: Meshing the geometry model.

Select 'Meshing --> Parameters' to open the meshing configuration panel and then set the parameters as show the next figure. In order to obtain the shortest possible time for meshing,it is recommended to run the process of meshing with the number of physical processors available to the machine.

Figure 11. Meshing panel


Then click on 'Mesh' button to starting the meshing. A panel appears to display meshing process information.

Figure 12. Meshing process log


Step 7: Execute the simulation. In order to obtain the shortest possible time for calculating the results,it is recommended to run the process with the number of physical processors available to the machine.

Select 'Calculate --> Execute' option to open simulation parameters. Then select the number of processors as the next figure show.

Figure 13. Execute panel


Then click on 'Execute' button to starting the simulation. A panel appears to display execute process information.

Figure 14. Execute process log


Step 8: Show Results. To get more information about the graphics panel advanced options (clicking on right button of the mouse over the panel) see Annex 1: Graphics Advanced Options.

Select 'Show Results --> Far Field --> View Cuts' option to show the cuts of the observation directions options.

Figure 15. Far Field cuts


Selecting other values for the component, step, frequency or cut parameters and clicking on 'Add Series' button a new cut will be added to the selected parameters. On 'Show Results --> Far Field' menu, other results are present such as 'View Cuts by Step' and 'View Cuts by Frequency' and this option display the values for one selected point for each step or frequency.

Select 'Show Results --> Radiation Pattern --> View Cuts' option to show the cuts of the radiation pattern options.

Figure 16. Radiation Pattern cuts


Selecting other values for the component, step, frequency or cut parameters and clicking on 'Add Series' button a new cut will be added to the selected parameters. On 'Show Results --> Radiation Pattern' menu, other results are present such as 'View Cuts by Step' and 'View Cuts by Frequency' and this option display the values for one selected point for each step or frequency.

Select 'Show Results --> Radiation Pattern --> View 3D Pattern' option to show the cuts of the radiation pattern options.

Figure 17. Radiation Pattern 3D


Changing values for step, frequency, component or filtering parameters the visualization for the new parameters will be shown.

Select 'Show Results --> View Currents' option to show the current density.

Figure 18. Current Density


Changing values for step, frequency, magnitude, component or filtering parameters the visualization for the new parameters will be shown.

Select 'Show Results --> View Charges' option to show the charge density.

Figure 19. Charge Density


Changing values for step, frequency, magnitude or filtering parameters the visualization for the new parameters will be shown.

Select 'Show Results --> Near Field --> View Near Field Diagram' option to show the observation points diagram. Previously, select the observation to visualize and the step and frequency on the next figure.

Figure 20. Near Field diagram selection


Figure 21. Near Field diagram


Changing values for incidence, magnitude, field or component parameters the visualization for the new parameters will be shown.

Select 'Show Results --> Near Field --> View Observation Points' option to show the observation points chart.

Figure 22. Near Field Observation Points cuts


Selecting other values for incidence, component, step, frequency or observation parameters and clicking on 'Add Series' button a new cut will be added to the selected parameters. On 'Show Results --> Near Field' menu, other results are present such as 'View Cuts by Step' and 'View Cuts by Frequency' and this option display the values for one selected point for each step or frequency.

Select 'Show Results --> View Impedance' option to show the impedance values for the simulated coaxial feed.

Figure 23. Impedance panel


Selecting other values for the step or return loss parameters new values will be displayed for the selected parameters.

Clicking on 'Chart' button when any columns selected on 'Results' table, a plot with the values will be opened.

Figure 24. Impedance chart