Reconstruction over a regular grid of antenna near field measurement based on irregular near field data

The aim of this study is the implementation and the validation of a technique for reconstructing the antenna near field in planar coordinate system. The near field samples over a regular grid are calculated from the irregularly near field samples which are randomly distributed over a planar surface. The spacing between consecutive samples can be almost larger than lambda/2. This irregularity can be attributed to probe positioning errors during the antenna under test characterization. The mathematical formalism and the stability of this reconstruction technique are presented and compared with some other techniques as Approximate Prolate Series (APS) and the classical Spline Cubic (SC) interpolation methods. The effect of reduced signal to noise ratio is taken into account in our analysis. The proposed method and the previously cited ones (APS, SC) have been implemented using Matlab software. The numerical validations show the efficiency and the stability of the proposed technique.