I know I probably didn’t phrase this correctly, but my English grammar is limited in this sort of stuff . I hope someone understands what I’m trying to say hah
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Depends on the shape of the antennae, it’s an entire engineering field how to design antennae to achieve desired radiation patterns [https://en.wikipedia.org/wiki/Radiation_pattern](https://en.wikipedia.org/wiki/Radiation_pattern)
No antennae radiates in a perfect 360 though, that’s one of the reasons that modern radio devices often have many antennae, so that one antennae could cover the not so good directions of the others.
The fields are 3D. Think about the earth’s magnetic field. It extends far into space and crates a sort of “bubble” that protects the planet from solar wind. When you lay a magnet down on a table and throw a bunch of iron filings down, they form all these field lines on the table. It may look 2D, but what you’re seeing is a single 2D slice of a larger 3D field. Like how a circle can be a 2D slice of a sphere. I hope this was your question!
A single “linear polarized” electromagnetic wave comes from a changing electric field, which generates a perpendicular changing magnetic field, which regenerates the changing electric field. The two fields are individually 2 dimensional, but because they are perpendicular the wave is 3 dimensional.
When two electromagnetic waves with the same frequency overlap and are 90 degrees out of phase (in phase means the peaks of the waves line up) they add up to form a more complex wave that is “circular polarized” where the individual fields rotate in 3 dimensions
Imagine a planet like the Earth. If it had a magnetic field 3d all around, it would protect agains solar radiation all the time all around. If it had 2d it would protect just one slice of tje surfere while the other is bombarded with cancer Rays.
Now. Look at the acutal Earth planet we live on. What kind of magnetic anti cancer solar Ray protection do we have? All around baby, so we must infer that Earths magnetic field (and fields in general) be the all-around and ‘3d’.
Unfortunalty we have a hard time to easely experiment on it at home. Yoy know the experiment whare yoy place a bar magnet under a piece of paper and then drizzle small Iron filings over it to show the magnetic lines? Thats a 2d slice of the magnetic field lines that goes all around. You can clean it up, turn the bar magnet and repeat, now yoy have a visual for these other 2d slice of the bar magnets magnetic field… continue to do this with in all of the 3d space around the magnet and not just the now 2 slices if the field, and you can see the 3d field all around the bar magnet.
It depends. In general, radiation is three dimensional but not necessarily in a perfect spherical shape. Dipoles for example radiate in a sort of “donut” shape (well, their power density does, which is what you can measure), wherein the closer you get to the axis the dipole is in, the lesser the radiation is.
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