Radix-2/4 Streamlined Real Factor FFT Algorithms

In this paper three Real Factor FFT algorithms are presented. Two of them are based on Radix-2 and one on Radix-4. The computational complexity of Radix-2 and Radix-4 is shown as order N ~ 2 2 1 Nlog 4 and N Nlog 4 ~ 2 8 1 respectively unlike their standard counterparts N Nlog 5 ~ 2 and N Nlog 4 ~ 2 4 1 . Moreover, the proposed algorithms also require fewer multiplications than their standard FFTs. We then show that the fixed point implementation of 'real factor' FFT can be modified, with unique scaling procedure, so that its noise to signal ratio (NSR) is lower than the NSR of standard FFT. Finally, implementation issues are presented which verify the suitability of the proposed 'real factor' FFT's.