Determination of sampling points for nearly DFT-equivalent almost-periodic fourier transforms

This paper presents analytical formulas for choosing sampling points required for almost-periodic Fourier transforms (APFT) of waveforms for the case of two fundamental frequencies. The generated sampling points are such that the resulting APFT is an optimal approximation of a corresponding two-dimensional discrete Fourier transform with respect to phase error, resulting in a numerically well conditioned transformation. The formulas may easily be implemented into existing APFT-based software packages.