7.1 Introduction7.2 Discrete Fourier Transform and the Finite-Duration Discrete Signals7.3 Properties of the DFT7.3.1 How Does the Defining Equation Work?7.3.2 DFT Symmetry7.3.3 DFT Linearity7.3.4 Magnitude of the DFT7.3.5 What Does k in X(k), the DFT, Mean?7.4 Relation the DFT Has with the Fourier Transform of Discrete Signals, the z-Transform, and the Continuous Fourier Transform7.4.1 DFT and the Fourier Transform of x(n)7.4.2 DFT and the z-Transform of x(n)7.4.3 DFT and the Continuous Fourier Transform of x(t)7.5 Numerical Computation of the DFT7.6 Fast Fourier Transform: A Faster Way of Computing the DFT7.7 Applications of the DFT7.7.1 Circular Convolution7.7.2 Linear Convolution7.7.3 Approximation to the Continuous Fourier Transform7.7.4 Approximation to the Coefficients of the Fourier Series and the Average Power of the Periodic Signal x(t)7.7.5 Total Energy in the Signal x(n) and x(t)7.7.6 Block Filtering7.7.7 Correlation7.8 Some Insights7.8.1 DFT Is the Same as the fft7.8.2 DFT Points Are the Samples of the Fourier Transform of x(n)7.8.3 How Can We Be Certain That Most of the Frequency Contents of x(t) Are in the DFT?7.8.4 Is the Circular Convolution the Same as the Linear Convolution?7.8.5 Is |X(w)| ≅ |X(k)|?7.8.6 Frequency Leakage and the DFTEnd of Chapter ExercisesEnd of Chapter Problems