Phase and Group Delays The output yIn] of a frequency-selective LTI discrete-time system with a frequency response H(e/o)exhibits some delay relative to the input x[n] caused by the nonzero phase response 0(o)=argH(e/o) of the system For an input x{]=AcoS(00n+),-<n<0 Copyright C 2001, S K MitraCopyright © 2001, S. K. Mitra 1 Phase and Group Delays • The output y[n] of a frequency-selective LTI discrete-time system with a frequency response exhibits some delay relative to the input x[n] caused by the nonzero phase response of the system • For an input ( ) j H e ( ) arg{ ( )}    = j H e x[n] = Acos(on + ), −  n  