Speed up of near-field physical optics scattering calculations by use of the sampling theorem

Physical optics scattering calculations performed on the NASA Deep Space Network (DSN) 34-meter beam-waveguide antennas at Ka-band requires approximately 12 hours CPU time on a Cray Y-MP2 computer-excessive in terms of resource utilization. The calculations are done two mirrors at a time. The sampling theorem is used to reduce the number of points on the second surface obtained by performing a physical optics integration over the first surface. The number of points required by subsequent physical optics integrations is obtained by interpolation. Time improvements on the order of 2 to 4 were obtained for typical scattering pairs