【摘要】 FFT算法是数字信号处理技术的关键部分,该算法的主要原理是按照标号的奇偶性对时域或频域序列进行分组,利用旋转因子的特性,得到多级蝶形运算结构,从而节省大量的运算量。FFT算法本身抽象,因此其算法的实现过程显得尤为重要。文章主要通过计算线性卷积和相关函数两种情况来说明FFT算法的使用方法,其中计算线性卷积包括两方面内容:重叠相加法和重叠保留法。文中对所有方法的计算过程都进行了详细介绍,结合例子给出对应的Matlab实现代码,对计算结果都进行了分析。更多还原

【Abstract】 FFT algorithm is the emphasis of digital signal processing technology. To divide the time or frequency sequence into short sequences according to the odd or even sample number is the algorithm principal. This algorithm can decrease plenty calculating times because of the rotation factor characteristics and butterfly shape structure levels. In this paper it shows the FFT algorithm application through calculating linear convolution and correlation function. There are two methods in calculating linear convolution including overlap-add and overlap-retain. It introduces the calculating steps about all methods and shows the Matlab code of example, analyzes the result of example explicitly in this paper.更多还原