Quote: Unlike lasers, radio waves spread out with distance. So ultra-precision isn't strictly necessary here.
That is not true in my experience. I've aligned a few wireless link antennas in my time and a few millimeters one way or another seems to make a big difference. This probably has far more to do with aligning the receiving dish than it does the transmitting antenna. The very fact that they do spread is probably what makes that alignment critical, as a few degrees off on a parabolic reflector can change the focus signficantly. I would imagine that a distance of about 22 miles would require a parabolic dish, but I could be wrong.
I imagine that a pair of yagi or log antennas would do the trick nicely. And at 22km, the beam spread will be many metres, rather than a pencil (remember those?) eraser tip (laser).
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