Use of sampling expansions in near-field-far-field transformation: the cylindrical case

A modified sampling technique is applied to the reconstruction of the antenna far-field pattern from near-field measurements on a cylinder. It is shown that, if a proper phase factor is singled out from the tangential components of the measured electric field, the samples spacing along the axis of the measurement cylinder increases linearly with the cylinder radius. Thus, when this radius is substantially larger than the antenna's dimension, the sample's spacing can be much greater than the half-wavelength spacing commonly accepted as the maximum possible one, without losing the computational efficiency of the standard approach.>