I was searching for helical antenna designs and stopped here to look around when I saw this antenna (below). I am guessing it has a somewhat omnidirectional characteristic that would be advantageous to put on a car/plane/helicopter to communicate with a helical "command station" antenna which can be manually pointed back.
- What is this antenna design called?
- What does the radiation pattern look like in three dimensions? Is it somewhat similar to a vertical dipole with isotropy in the horizontal plane and nulls at the top and bottom, or is it substantially different?
- What about polarization - linear? circular? azimuthal? mixed?
I've tried a translation, but it does not seem to describe the antenna itself. These can also be seen at the extreme left of the second image.