A Near to Far-Field Transformation from Plane-Polar Near-Field Measurements Affected by 3-D Probe Positioning Errors

In this work, an effective algorithm aimed to compensate known 3-D probe positioning errors corrupting the near-field (NF) data in the near-to-far-field transformation (NTFFT) with plane-polar (PP) scanning is developed and numerically assessed. Initially, the so named k-correction is adopted to compensate the positioning errors associated with the deviation from the scanning plane. Next, an iterative approach is properly exploited to retrieve the NF data at the points specified by the nonredundant sampling representation from those computed at the previous step and now affected by 2-D positioning errors. At last, once the correctly distributed PP data have been accurately recovered, those necessary to execute the classical plane-rectangular NTFFT are efficiently obtained by exploiting a 2-D optimal sampling interpolation algorithm. This latter has been developed by exploiting the nonredundant sampling representations and choosing an oblate spheroid to model the antenna. A wide range of numerical results are shown to validate the effectiveness of the developed approach.