New advanced methods of polarization manipulation are gaining momentum in electromagnetic engineering community as we proceed on the path of higher frequencies and aggressive scaling. Circularly polarized (CP) beams are matter of interest, because of the inherent advantages of circular polarization, among which we may mention the absence of a specific alignment need between transmitting and receiving terminals, a higher resilience to fading, and an increased penetration capability through obstacles; this is the reason why devices operating in circular polarization regime are spreading and evolving fast in applications ranging from health engineering to remote sensing, telecommunications, and radar.