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As a complete aside from most of the conversation happening here..

The ISS uses mainly circular polarisation in their radio communications because horizontal flips to vertical in a range of 15 minutes, relative to position over the Earth (90 minute period).

A horizontal antenna _can_ receive a vertically transmitted signal, with a 22 dBi loss. The reverse is also true. However, if a vertical or horizontal antenna receives a circularly polarised radio signal, the loss is only 3 dBi.*

Spoken as a user and experimenter of amateur radio.

* And I also found a link showing experimental loss when one receives a wrong "handedness" of circular polarisation. There is a clockwise and counter-clockwise polarisation as well. Theoretical maximum loss is also around 22 dBi, the same if you used a vertical to receive a horizontal.

So far, the types are: Horizontal, Vertical, CW circular, CCW circular, CW elliptical, CCW elliptical. Admittedly, I have never done anything with elliptical, but is noted here for completeness.



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