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does this code cotain the transform of the near field to the far field ?
You'll need to set up an 'infinite sphere' for far or near field under radiation. The 3d plot is pretty easy to get as a report but have a look at the coordinate sys on the 3d plot - the phi and theta are reversed. Something to keep in mind when you want a specific cut.
Generally all "transducers" antennas, electrical, but sonic also, generate a pattern that change its parameters along the transmission axis. This change is smooth but for classification, has been creeted almost 2 zone: the near fiels (also called Fresnel Region) and the far field (also called Fraunhofer region). Generally the far field (...)
Using existing FDTD code is not a good way to go. You would need to assign a distributed excitation, and the phase difference in your measurement would need to be changed to time delay. Depending on your measurement grid, this might not be easy to assign accurately. Suppose you have done a "near field" measurement, if you don't need to do the pr
I believe you will need a technique originally developed for antenna measurements: near-field to far-field transformation. I did google search for "near-field to far-field" and FDTD, and got about 10 pages worth of (stuff).
Hi, I also recommend to write your matlab script as Kit recommends. Look into some theory of antenna measurement, near to far field transformation can be treated as Fourier transformation which is very simple in Matlab! Look into attachment how it can be made - Usually we have defined sources in cartesian coordinates (magnetic currents [b
Hi, guys! I became interested deeper into zones of antenna - I mean Rayleigh and Fresnel as "near zone" and Fraunhofer as "far field". I need your comments... Is the difference between these zones only in simplifying Green function exp^{-jkR}/R resulting in Fourier transform when considering far field? Or there are some next effects (...)