Discrete-Time Fourier Transform We will assume that the phase function A(o) is restricted to the following range of values π≤(0)<兀 called the principal value Copyright C 2001, S K. MitraCopyright © 2001, S. K. Mitra 6 Discrete-Time Fourier Transform • We will assume that the phase function (w) is restricted to the following range of values: called the principal value −   (w)  