Beam array scattering by wedges and rectangular cylinders

Scattering by an obstacle in the near field of a radiating aperture can be obtained by superimposing many much simpler omnidirectional scattering solutions. These sources must be closely spaced in the aperture with relative amplitudes corresponding to the aperture field distribution. Highly accurate results can also be obtained with fewer basis solutions if they are beam solutions with the beams arranged in a Gabor lattice. Beam solutions are obtained from omnidirectional source solutions by substituting appropriate complex source coordinates for the real source coordinates. This procedure has already been used for antenna aperture scattering by local half planes and wide slits, where the main results are for forward scattered fields, and also for rectangular cylinders where backscattered fields are also shown. Back radiation from an aperture depends on aperture edge diffraction. This is not specified in a beam array representation, so the total backscattered field cannot be known. Here we revisit earlier solutions to determine how seriously back radiation from the aperture affects the numerical results and to improve our representation of both the radiation fields of an aperture in isolation and the total back scattered fields of an obstacle in the vicinity of the aperture.