Reference books: 1.A.V.Oppenheim and R.W.Schafer, Digital Signal Processing,1975 2.S.J.Orfanidis,Introduction of Signal Processing,Prentice Hall,1998,1. A.V.Oppenheim and R.W.Schafer, Digital Signal Processing, 1975 2. S.J.Orfanidis , Introduction of Signal Processing, Prentice Hall,1998, Reference books: