Fast Fourier Transform preprocessing for accelerated plane wave based spherical near-field far-field transformation

Abstract

Near-field measurement and transformation techniques are widely applied to characterize the radiation pattern of antennas. Spherical near-field measurements have been researched widely and various techniques with different probe compensation capabilities and complexities exist. Among those techniques applicable for (almost) arbitrary probes and based on spherical wave translations, the crucial computational relaxations have been gained through the use of a Fourier Transform based preprocessing of the measurement data. It is shown in this paper that the same Fourier Transform based preprocessing step can be applied in conjunction with the plane wave based probe-corrected near-field far-field transformations. The collection of probe signals is split into smaller sub sets by an Inverse Fast Fourier Transform. These sub problems can be solved with a reduced overall complexity and also a full probe correction is achieved.