An Efficient Two-Dimensional FFT Algorithm

A new version of the radix-2 row-column method for computing two-dimensional fast Fourier transforms is proposed. It uses a ``multiple vector'' FFT algorithm to compute the transforms of all the columns in an array simultaneously while avoiding all trivial multiplications. The minicomputer implementation of the algorithm runs faster than the 2 × 2 vector radix FFT algorithm. Analysis of the numbers of complex additions and multiplications required indicate that implementations of the radix-4 row-column FFT and 4 × 4 vector radix FFT on the same minicomputer would run slower than the multiple vector implementation.