Computation of the Fast Fourier Transform from Data Stored in External Auxiliary Memory for Any General Radix r=2n, n ≥ 1

A general method is presented for the computation of the fast Fourier transform from data stored in external auxiliary memory, for any general radix r = 2ⁿn ≥e external data storage is necessitated whenever the internal computer memory is limited. The general radix requirement arises in the tradeoff in serial FFT processor machines, between the number of passes required to address storage and the number of equivalent sparse matrix multiplicative operations required to compute the fast Fourier transform.