一种改进的滑动窗FFT递推算法

在信号谱线分析中,经常用到滑动窗的FFT计算,由于传统的FFT在N值较大和滑动步进较小时,计算量较大,在实时通信系统中难以实现,本文提出一种连续滑动窗的递推FFT算法,该算法充分利用了前窗的计算结果并将输入序列转换为一个输入端仅有少数非零点的特殊序列,不仅降低了计算量,而且提高了使用的灵活性和实时性。

An Improved FFT Algorithm Based on Successive Gliding Window

The FFT computation based on successive gliding window are often be used in the signal spectral analysis.When the window-order is larger or the gliding-step is smaller,this algorithm can't he realized in the real time system for the enormous computa- tional complexity.In this paper,an improved algorithm based on recursive Pruning FFT is proposed.The improved algorithm is fully u- sing the last window FFT results and converts the input sequences to a special pruning sequences which only contains few nonzero data points.This improved algorithm not only reduces the calculation of the discrete Fourier transform(DFT),but also improves the flexibility and real time implementation.