Generalized twiddle factor index mapping of radix-2 fast Fourier transform algorithm

In pipelined implementation of the fast Fourier transform (FFT), memory is required to store the precomputed twiddle factor in memory. Twiddle factor index-mapping is used for address generation to access the memory. In this work we consider generalized radix-2 FFT architecture, proposed the generalized twiddle factor index mapping algorithm for twiddle factor memory and also calculate number of all possible algorithms. It is shown that the index mapping algorithm can be used for all possible algorithm decomposed of radix-2.