Discrete-Time Fourier Transform We will assume that the phase function 0(o) is restricted to the following range of values π≤6(0)<T 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)