Scattering Characteristics of an Electrically-large Aircraft Object Illuminated by Bessel Vortex Beams

Based on the excellent and broad prospect of the vortex beams in military application, it is necessary to evaluate the scattering characteristics of classical Bessel beam upon a perfect electrical conductor (PEC) blunt cone model of aircraft structure. First, a Bessel beam is expanded by a series of plane wave spectra. Then, combining the physical optics (PO) method, the scattered field of the object fitted by facet elements can be calculated. The amplitude, phase, and orbital angular momentum (OAM) spectra of scattered field for different object attitudes are discussed in detail. The results show that the backward scattering still retains good OAM characteristics, and which are distorted with the increase of oblique angle. Besides, the backscattering radar cross section (BRCS) of aircraft are also calculated and analyzed, and the scattering results of degenerated zero-order Bessel beam and plane wave are compared to verify the correctness of the proposed theory. Compared with plane waves, object scattering of vortex beams provides a new degree of freedom, providing more information for object detection.