On the Direct Non-Redundant Near-Field-to-Far-Field Transformation in a Cylindrical Scanning Geometry

The experimental validation of a direct near-field-to-far-field transformation technique with cylindrical scanning is presented in this paper. The technique requires a minimum number of near-field measurements. It is based on a non-redundant sampling representation of electromagnetic fields using a spherical modeling of the antenna under test. It allows the evaluation of the antenna's far field directly from the acquired non-redundant near-field data without interpolating the data. The good agreement between the reconstructed far-field patterns and those obtained via the classical cylindrical near-field-to-far-field transformation expressed the effectiveness of the technique. The technique exhibits the very interesting property of eliminating the characteristic ripple caused by the discontinuity of the near field at the edges of the measurement cylinder.