Simple method for any planar wiggler field simulation

This paper deals with a nonstandard method for calculating the magnetic field of planar wigglers and undulators consisting of pure permanent magnets. This method of calculation is based on certain properties of the Fourier transform. It allows the analytical expression of the Fourier transform for the planar magnetic fields through the wiggler's geometry and magnetization of its blocks. The upper theoretical limit for the amplitude of the magnetic field is derived and matched with the field amplitude of planar wigglers with standard designs. The property of universality for planar wigglers is also taken into consideration as it may greatly simplify the analysis of magnetic fields for wigglers with different designs.