A new nesting scheme of PFA [prime factor algorithm]

A nesting scheme type of prime factor algorithm (PFA) is introduced. It takes advantage of both the PFA and the Winograd Fourier transform algorithm (WFTA) by developing a new nesting scheme and modifying the small-N discrete Fourier transform (DFT) algorithms. This new nesting scheme will not expand the data in the nesting multiplication part. It requires far fewer multiplications and fewer additions than the PFA. In addition, data transfer between the main array and the temporary array, which is needed by the WFTA, is avoided, and it can be implemented in place and in order