Efficient realisation of discrete Fourier transforms using the recursive discrete Hartley transform

The authors present the results of their study using a recursive discrete Hartley transform technique to compute discrete Fourier transforms. They also introduce an improved in-place and in-order prime-factor mapping to effectively realise composite-length DFTs. In using these new techniques, the speed of computation is comparable to that of the Winograd Fourier transform algorithm (WFTA), whereas the program size of the present approach is much smaller than that of the WFTA. This approach is most suitable for the cases where there are restrictions on program lengths.