Using the Macro

Execute the CM_synthesis_and_design.lua application macro in POSTFEKO to calculate the weighted sum for the characteristic modes of interest.

  1. Open antenna_plate.fek in POSTFEKO.
  2. Execute the CMA_synthesis_and_design.lua application macro in POSTFEKO.
    The Characteristic mode synthesis and design dialog is displayed.
    Figure 1. The Characteristic mode synthesis and design dialog.


  3. In the Select CM data drop-down list, select antenna_plate.CharacteristicModeConfiguration1.CharacteristicModes1 and click OK.
    The second Characteristic mode synthesis and design dialog is displayed.
    Figure 2. The Characteristic mode synthesis and design dialog.


  4. In the Frequency (Hz) drop-down list, select a frequency.
  5. In the Definition method drop-down list, select one of the following.
    • Select Synthesis, to use the modal weighting coefficient as the weight for each mode interest.
      Note: The synthesis mode requires the modal excitation coefficients to be calculated.
    • Select Design, to specify the weighting coefficient manually for each mode of interest.
  6. Select the modes of interest to calculate the weighted sum.
    Tip: Use the button to select all modes and the button to clear all modes.
  7. If Design is selected, enter the weights for the selected modes, for each mode.
    • Enter a value for the real part of the complex weight Weight x:Re.
    • Enter a value for the imaginary part of the complex weight Im.
  8. Specify the results to calculate a weighted sum for the characteristic modes.
    • Select the Include far fields check box, to calculate a weighted sum for the far field data.
    • Select the Include near fields check box, to calculate a weighted sum for the near field data.
    • Select the Include surface currents check box, to calculate a weighted sum for the surface current data.
    • Select the Include wire currents check box, to calculate a weighted sum for the wire current data.
  9. Click Calculate to start the calculation process.
    The following dialogs are displayed.
    Figure 3. The Characteristic mode synthesis and design (progress) dialog.


    Figure 4. The Characteristic mode synthesis and design (Done) dialog.


  10. View the results under stored data.
    Note: The label convention for the synthesis definition methods are:
    • Synthesis: <requestname>_SM1__M20.
    • Design: <requestname>_DM1__M20.
    An example using the synthesis definition method, summing modes 1 to 20 at 830 MHz for the antenna plate example. The results for the far field and currents are shown. The full solution (MoM) is compared with the synthesis method.
    Figure 5. Example comparing the full solution to the synthesis definition method (using modes 1 to 20) for the far field.


    Figure 6. Example of the surface current for the synthesis definition method (using modes 1 to 20).


    Figure 7. Example of the full solution for the surface current.