New DIT Radix-8 FFT Butterfly Structure

새로운 DIT Radix-8 FFT 나비연산기 구조

Jang, Young-Beom

  • Received : 2015.05.29
  • Accepted : 2015.08.06
  • Published : 2015.08.31


In FFT(Fast Fourier Transform) implementation, DIT(Decimation-In-Time) and DIF (Decimation-In-Frequency) methods are mostly used. Among them, various DIF structures such as Radix-2/4/8 algorithm have been developed. Compared to the DIF, the DIT structures have not been investigated even though they have a big advantage producing a sequential output. In this paper, a butterfly structure for DIT Radix-8 algorithm is proposed. The proposed structure has smaller latency time because of Radix-8 algorithm in addition to the advantage of the sequential output. In case of 4096-point FFT implementation, the proposed structure has only 4 stages which shows the smaller latency time compared to the 12 stages of Radix-2 algorithm. The proposed butterfly can be used in FFT block required the sequential output and smaller latency time.




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Supported by : 상명대학교