The DFT as Convolution or Filtering ∗
نویسنده
چکیده
A major application of the FFT is fast convolution or fast ltering where the DFT of the signal is multiplied term-by-term by the DFT of the impulse (helps to be doing nite impulse response (FIR) ltering) and the time-domain output is obtained by taking the inverse DFT of that product. What is less well-known is the DFT can be calculated by convolution. There are several di erent approaches to this, each with di erent application.
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