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mel

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mel last won the day on February 6

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About mel

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  1. mel

    How to recover information in file.out

    The OUT file should give the element numbers. Use Find Elements on the Mesh tab in POSTFEKO.
  2. mel

    Mesh problem with coaxial cable.

    Change the Selection Type to Edges / Wires and click on the line. Right click and select Properties and set a local wire radius or local mesh size, whatever is too large.
  3. mel

    FDTD problem

    Hi John This is exactly what I alluded to earlier. The pin feed is not ideal and will introduce differences and standing waves. And it could very well be that the 50 Ohm loads I suggested are not the best match for the waveguide which will also cause standing waves.
  4. mel

    FDTD and SAR Calculations

    The hybrid FEM/MoM is well suited for SAR. See the Example Guide example F1 "Exposure of Muscle Tissue Using the MoM/FEM Hybrid For human phantoms, Altair Connect has a couple of phantoms for free download.
  5. mel

    FDTD problem

    Yes, set a longer "Maximum time interval". You can also add say 50 Ohm loads to the ports - lossless models tend to you require longer runtimes for the wave to propagate back and forth in the grid.
  6. mel

    Active Element Pattern and Scan Blindness

    Hi Bidisha Why have you chosen a 25 element array? Seems the article is computing an infinite array. You can simulate an infinite array with the Periodic Boundaries found on the Construct tab. The Example Guide in the help folder has an example, the Jerusalem Cross .
  7. Hi Kuzi Would these options under the plane wave source help?
  8. mel

    FDTD and SAR Calculations

    Hi Sutton FDTD does not yet support SAR. Are you trying FDTD to compare with MoM?
  9. Hi pmcardle The incident field is indeed excluded in the far field.
  10. mel

    CMA Annular ring gap around the feed

    Hi RF I still can't understand what you are doing. How about some screenshots from your CADFEKO model?
  11. mel

    FDTD problem

    Hi John Have a look in the help folder of Feko for the ExampleGuide model Example-H04-Optimise_Waveguide_Pin_Feed_Location It contains a simple pin feed for a waveguide. If you can use a different solver apart from FDTD I would still recommend the FEM since the modal port is an ideal port and applies the correct mode (fields) to the waveguide as if the waveguide stretches to infinity away from the port. Waveguide pin feeds are usually not ideal over bandwidths.
  12. mel

    WARNING 2757 Consequences

    Hi Sutton304803 If the warning is given, Feko still applies the skin effect, but the accuracy could be compromised. The warning is given if the triangle edge length is similar as the thickness you specified for the finite conductivity elements. You can check the OUT file for the triangle element numbers. to which the warning applies and search for these elements in POSTFEKO under the Mesh tab, Find Elements. My guess would be the warning is given for the elements on the 2 vertical sides of your conductor - these triangles are probably much smaller than those on top and bottom sides of the conductor. (The skin effect approximation also requires that a good conductivity is used where conductivity sigma is much larger than the product 2 pi f eps0) Also just check if this isn't related to the model unit - i.e. your model unit is meters but you specified the thickness of the elements in units of mm.
  13. Hi pmcardle You could just request a scattered near field sufficiently far away from the object.
  14. mel

    Element Gain Pattern

    Hi Bidish Usually you would have to excite just the one element you want the pattern for and load all the other elements with typically 50 Ohm. You can do it in a single model by using multiple configurations in CADFEKO. You can view a video of how multiple configurations are setup here: https://altairuniversity.com/learning-library/multiple-configurations-with-feko/
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