Aut Far-Field Pattem Reconstruction from A Reduced Set of Spherical Near-Field Data Collected in Presence of An Infinite Perfectly Conducting Ground Plane

The non-redundant sampling representations of electromagnetic fields and the image principle are properly applied in this work to develop an effective probe-compensated spherical near-field to far-field (NFTFF) transformation, which makes use only of the NF data measured over the upper hemisphere, due to the presence of an infinite perfectly conducting ground plane. According to these representations, the considered antenna under test (AUT) and its image are assumed as enclosed in a surface consisting of a cylinder ended in two half-spheres. Then, an efficient 2-D optimal sampling interpolation scheme is used to reconstruct the NF data required by the standard spherical NFTFF transformation from the NF samples collected over the upper hemisphere and from those properly synthesized from these last over the lower one. Numerical examples are shown to assess the effectiveness of the developed non-redundant spherical NFTFF transformation.