The 3D approximation of antenna radiation patterns

The method of bilinear interpolation by cubic spline functions implemented in Matlab was utilized to calculate the full 3D approximation of antenna radiation patterns only from its two basic orthogonal cuts for an arbitrary antenna diagram. Only the type of radiation pattern has an influence on the approximation error. For axially symmetrical radiation patterns the error is negligible. We can talk only about the maximal error because it is spatially dependent and therefore it cannot be averaged. The comparisons with measured radiation patterns were presented as well. As a general conclusion, it can be said that the presented method implemented in Matlab is a very useful and helpful tool for estimation of the three-dimensional antenna radiation patterns from spatial cuts. It can be used not only for the needs of propagation modelling but also for the measured antenna data processing.