Abstract: In this paper, we discuss FFT and Decision diagrams (DD) methods for calculation of discrete spectral transforms of signals represented by large sequences. It has been pointed out that DD-methods are performing of FFT-like algorithms over decision diagrams instead of vectors. Differences between these methods are discussed and it is explained where from DD-methods take the advantages in processing of large functions.
Keywords: Digital signal processing, FFT, Haar transform, Walsh transform.