Patent US 8,458,561

The method allows to obtain, starting from an initial S-random interleaver permutation stored in memory devices and having a size N, a final S-random permutation having a smaller size K<N by successive pruning operations which yield the final permutation, through an iterative process which is performed by using electronic processing devices, and in which in successive steps selected elements are eliminated in accordance with predetermined criteria. The final permutation is generated using a reference vector having a dimension or size equal to that of the initial permutation. Said reference vector is generated by said processing devices in such a way that for each pruning step, if the element has been eliminated on the basis of a predetermined criterion, one element of the reference vector is generated in such a way that the value and the position thereof in the reference vector are indicative of the value of the element eliminated.