1. Husheng Li, UTK-EECS, Fall 2012

2. The specification of filter is usually given by the tolerance scheme.  Discrete Fourier Transform (DFT) has both discrete time and discrete frequency.  DTFT has a continuous frequency, which is difficult to process using digital processors.  DFT has a fast computation algorithm: FFT.

8.  The sequence having DFS equaling the frequency domain sampling results from the aperiodic sampling.

12.  Since there is a fast computation algorithm in DFT, we can compute convolution via DFT:  Compute the DFTs of both sequences  Compute the product of both DFTs.  Compute the output using IDFT.  The length of DFT should be properly chosen; otherwise we will see aliasing.