Lecture 20: Discrete Fourier Transform and FFT
نویسنده
چکیده
basically saying we care not about the rest of x[n], since it is zero. Pretend that it is periodic for analysis purpose since for the DFT it makes no difference. Defined only for 0≤ n,k ≤ N−1. The rest is zero. This means the inherent periodicity is not represented. Notation x[n] DFT ←→ X [k] Lots of properties (similar to DFS) circular convolution is important. Given x1[n] and x2[n], form x̃1[n] and x̃2[n]. Periodic convolution is
منابع مشابه
Data - sparse matrix computations Lecture 2 : FFT - The Fast Fourier Transform Lecturer : Anil Damle
It is without a doubt, one crucial piece of the toolbox of numerical methods. The FFT or Fast Fourier Transform is a fast algorithm used to compute the Discrete Fourier Transform. It is one of the most common discrete transforms used today. Note: While many other algorithms used throughout this course can be coded up for use in other projects, you shouldn’t attempt to do this with the FFT. The ...
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تاریخ انتشار 2001