Scattering Characteristics of Vortex Electromagnetic Waves for Typical Targets

Vortex electromagnetic (EM) waves, which carry orbital angular momentum (OAM), offers a new degree of freedom for radar detection, although to date few researches on vortex EM waves scattering characteristics for typical targets have been reported. In this paper, we investigated the backscattering characteristics of vortex EM waves for targets, i.e., corner reflectors, and flat plate. Experiments are carried out in an anechoic chamber to measure the radar cross section (RCS) of the targets, and the results indicate that for corner reflectors the RCS fluctuations of vortex EM waves are similar to that of the plane EM wave, whereas for the flat plate, RCS varies with OAM mode. The significance of this work exists in its pioneering character, which paves the way for revealing EM scattering characteristics in OAM domain.