Two efficient procedures to correct the positioning errors in the plane-polar scanning

Two techniques to effectively compensate known positioning errors in a plane-polar near-field–far-field (NF–FF) transformation, using a minimum number of NF data and adopting an oblate ellipsoid to shape the considered antenna, are proposed and validated through experimental proofs. The former makes use of the singular value decomposition method to recover the voltage samples which would be acquired by the probe at the points fixed by the non-redundant sampling representation from the collected positioning error affected ones, whereas the latter employs an iterative scheme. The NF data required by the classical NF–FF transformation with plane-rectangular scanning are then efficiently evaluated via a two-dimensional optimal sampling interpolation formula. The effectiveness of the proposed techniques is assessed by experimental tests performed at the Antenna Characterisation Lab of the University of Salerno.