The problem of three-dimensional scattering from anomalies buried in the earth is considered. In the general situation, this requires the fields to be evaluated using two-dimensional numerical integration. In this or the related inverse problem, subsurface characteristics are extracted from a two-dimensional grid of surface field measurements. This grid of points is computed with time-saving two-dimensional digital Fourier transforms, i.e., with plane-wave analysis. A simple method for selection of sampling windows and increments in x and κ (wavenumber) space which bounds and minimizes aliasing errors is presented and used. The theory is applied to the canonical problem of magnetic dipole excitation of a buried cylinder.