Experiments in Sampling, Reconstruction, and Filtering
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چکیده
The term FFT is used to signify a specific method to compute the DFT in an efficient manner. While a transform in its own right, the DFT/FFT can be interpreted in terms of the CT-Fourier transform for a sampled signal x(t). Let us consider a signal x(t), sampled at the time instants nT, n = 0,1,...N-1, and suppose that the signal is 0 outside the sampled interval [0, (N-1)T]. The Fourier transform of this signal is
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