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Impressive new antenna modelling graphics code from KD5ONS


Ham Radio Nerd
Apr 14, 2002
This is cross posted from the Elecraft reflector. The video is so impressive and informative that I wanted to make others aware of the project. See below and enjoy!


I translated some antenna theory into computer graphics. I modeled the electric field for a 1/4 wave dipole, a 1/2 wave dipole direct part, and 1/2 wave dipole direct+reflected parts. You can view the antennar adiation patterns by displaying a mesh, or shaded faces, or as nodes. Changing the height animates the radiation pattern so you can see how the electric field strength changes.

I made a video of the application in action. It demonstrates why a 1/4 wavelength antenna works best when its feedpoint is at ground. It also shows how a 1/2 wave dipole reacts when it gets too close to ground. The code runs under Windows but I wrote it using Linux, wine, and Virtual Box. It should run under Linux, Mac, or Windows operating
systems. But, for now, a video is available at http://bacona.design/video.html

I use the sedimentary system so the newest files float on top. The pdf below the video shows how I translated the E field equations into computer code.

http://bacona.design/video/Translate reflected equation.pdf

My next step is to find the Bessel function code I wrote. Or rewrite it
to model loop antennas as well. After that attempt to unravel the
equations around Yagi-Uda antennas. A good rainy season project :)

73, Kevin. KD5ONS

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