Skew symmetry detection using the Walsh spectral coefficients

In this paper, we present a new method to detect skew equivalent and skew non equivalent symmetric variables in Boolean functions. The method uses the Walsh spectrum of Boolean functions and is extremely fast in detecting assymetries to avoid more spectrum calculation. When the symmetry, exists, the method needs half of the spectral coefficients to detect it. Experimental results on a large number of functions show that our approach is very efficient