§4.2 The Frequency Response H(ei),in general,is a complex function of o with a period2π It can be expressed in terms of its real and imaginary parts H(e)=Hre(ej)+j Him(ei) or,in terms of its magnitude and phase, H(eio)=H(eio)川e(o) where θ(o)=argH(ejo)§4.2 The Frequency Response • H(ejω), in general, is a complex function of ω with a period 2π • It can be expressed in terms of its real and imaginary parts H(ejω)= Hre(ejω) +j Him(ejω) or, in terms of its magnitude and phase, H(ejω)=|H(ejω)| eθ(ω) where θ(ω)=argH(ejω)