ICTACT Journal on Communication Technology (Mar 2012)
A RADIX-4/8/SPLIT RADIX FFT WITH REDUCED ARITHMETIC COMPLEXITY ALGORITHM
Abstract
In this paper we present alternate form of Radix-4/8 and split radix FFT’s based on DIF (decimation in frequency) version and discuss their implementation issues that further reduces the arithmetic complexity of power-of-two discrete Fourier Transform. This is achieved with circular shift operation on a subset of the output samples resulting from the decomposition in these FFT algorithms and a proposed dynamic scaling. These modifications not only provide saving in the calculation of twiddle factor, but also reduce the total flop count to ˜4Nlog2N almost 6% fewer than the standard Radix-4 FFT algorithm 2113log12NN? , 5% fewer than the standard Radix-8 FFT, and 273log9NN? , 5.5% fewer than the standard split radix FFT. Keywords: DFT (Discrete Fourier Transform), FFT (Fast Fourier Transform), Radix-4(R4), Radix-8(R8) and Split Radix (SR) FFT and Flop Count