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In a dipole antenna or any other pole like antenna, there is supposedly a ground on one side causing the current to flow away and towards the ground towards the feed, but if the whole antenna itself is a good enough conductor with free electrons, how does the earthing work? Is it necessary to have an antenna such that it's resistance is higher than the ground?

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    \$\begingroup\$ In a dipole antenna, there's no ground on one side. So, no, your considerations make no sense. The electron model is not useful to model antennas – it's literally the field where you think of currents as the phenomenon that leads to waves, so, while describing the same thing as in say, solid state electronics, the "pool of electrons" model isn't sufficient to explain antennas. \$\endgroup\$ – Marcus Müller Apr 28 at 8:55
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As usual, electron-based thinking will lead you astray. A metal or other conductor has mobile electrons which are usually referred to as "free", but there is an overall balance of their number with the number of protons in the metal, so they are not a "surplus". The nearest thing to a surplus electron source might be a N-type semiconductor.

Dipoles and monopoles-with-ground are usually considered separately. Dipoles aren't grounded. My antenna theory is rusty so I'm going to refer you to the internet.

The important number is not resistance but impedance at the particular frequency of interest. The resistance of a good antenna is as close to zero as possible.

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  • \$\begingroup\$ +1 for "As usual, electron-based thinking will lead you astray." @user163416: Instead of "free electrons" just think of it as charge mobility. Charge mobility will allow charge flow which is current. \$\endgroup\$ – Transistor Apr 28 at 12:21
  • \$\begingroup\$ @Transistor it comes up so often I'm thinking of writing some sort of FAQ on the subject \$\endgroup\$ – pjc50 Apr 28 at 16:36
  • \$\begingroup\$ That could be worthwhile. I found myself answering so many LED questions that I created my own site. (See my profile.) I regularly post images from there into EE.SE. I haven't figured out how to make money from it though! \$\endgroup\$ – Transistor Apr 28 at 16:58

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