Can one construct a filter out of nothing but pure metal that will pass only right circular polarized radiation and reflect left circularly polarized radiation?
What would it look like? A helical spring in a tube?
What about a twisted metalic ribbon inside a circular conducting tube?
An axial mode helical antenna transmits circularly polarized radiation.
If I put an axial mode antenna (perhaps with a resistive load?) in a waveguide, can I create a filter that passes only say left circularly polarized radiation?
I would ideally like to do it with only conductive (i.e. not resistive) material.
I would also like it to reflect (not absorb) radiation of the opposite circular polarization.
Can someone tell me how to do this?