83.1 Discrete-Time Fourier Transform Xr(eo)and xim(eo)are, respectively, the real and imaginary parts of x(eJo), and are real functions of o 。x(e°) can alternately be expressed as X(ejo)= X(ejo) eje(@) where 6(0)=arg{X(e)}§3.1 Discrete-Time Fourier Transform • Xre(ej) and Xim(ej) are, respectively, the real and imaginary parts of X(ej) , and are real functions of  • X(ej) can alternately be expressed as X(ej) = | X(ej) |ej() where () = arg{X(ej) }