Example 1: 16x16 Short Dipole Array with Uniform Algorithm

This case explains how to use the uniform algorithms to calculates the pointing parameters in a bidimensional short dipole array.

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 Set the simulation parameters as shown.

Select Simulation - Parameters option, set the parameters and save it.

Figure 2. Simulation panel

Step 3 Create the array.

Click on Source - Dipole - Dipole Array to create an array of 16x16 electrical short dipoles, with a spacing of 0.04 m, that are oriented following the y-axis. The array is located on the XY plane. The spacing of 0.04m is equivalent to a spacing of 0.267 in units of lambda, at a frequency of 2 GHz.

Figure 3. Dipole Array panel

Step 4 Feed the array.

To set the feeding of the array select Source - Antenna Feeding and the following panel will open.

Figure 4. Antenna Feeding panel

This is the default setting. To use the uniform algorithm click on Tools - User Function and select the corresponding function. NOTE To use the bidimensional uniform function it is needed to download both the bi-dimensional and the unidimensional functions.

Figure 5. Bi-dimensional Uniform function

A path has been selected by default so the files will be created on the mydatafiles folder in the newFASANT directory.

Figure 6. Bidimensional Uniform function

The next step is generating the text file. To do so click on Tools - Calculator and write the call to the function.

Figure 7. Calculator panel

The parameters to set are:
  • d1 element spacing of the array in the x-axis in units of lambda
  • N1 number of array elements of the array in the x-axis
  • d2 element spacing of the array in the y-axis in units of lambda
  • N2 number of array elements of the array in the y-axis
  • theta beam angle, in degrees
  • phi azimuth angle, in degrees

In this case, set the parameters as shown. Angles of theta=45º and phi=0º are selected as an example.

Figure 8. Calculator panel

The text file will be automatically generated in the mydatafiles folder.

Figure 9. Results file

Now, apply these results to the array created before by clicking on Source - Antenna Feeding.

The panel shown before will appear. To use the weights and phases calculated with the uniform algorithm, click on Import.

Figure 10. Amplitude/Phase File panel

Select the corresponding file and save the feeding.

Step 5 Create ground plane.

In order to avoid unwanted radiation to go below the array, create a ground plane using the plane command, or Geometry - Surface - Plane. The array is situated in the XY plane with z=0, so the z coordinate has to be negative.

Figure 11. Plane parameters

View of the dipole array.

Figure 12. Array view

Step 6 Solver parameters.

Select Solver - Advanced Options and set the parameters as shown.

Figure 13. Solver Advanced Options panel

Step 7 Meshing the geometry model.

Select Mesh - Create Mesh to open the meshing configuration panel and then set the parameters as show the next figure.

Figure 14. Meshing panel

Click on Mesh.

Step 8 Execute the simulation.

Select Calculate - Execute option to open simulation panel.

Figure 15. Calculate panel

Step 9 Show Results.

The radiation cuts can be visualized by clicking on Show Results - Radiation Pattern - View Cuts.

Figure 16. Radiation Pattern Cuts

The radiation pattern can be visualized by clicking on Show Results - Radiation Pattern - View 3D Pattern.

Figure 17. Radiation Pattern 3D

Figure 18. Radiation Pattern 3D