Discrete-Time Systerms: Examples ° Accumulator-y{n]=∑x(] ∑x[(」+x{]=yn-1]+x The output y[n]at time instant n is the sum of the input sample x[n] at time instant n and the previous output yln-l at time instant n-1. which is the sum of all previous input sample values from -oo to n The system cumulatively adds ie,it accumulates all input sample values Copyright C 2001, S K. MitraCopyright © 2001, S. K. Mitra 3 Discrete-Time Systems: Examples • Accumulator - • The output y[n] at time instant n is the sum of the input sample x[n] at time instant n and the previous output at time instant which is the sum of all previous input sample values from to • The system cumulatively adds, i.e., it accumulates all input sample values =  =− n y n x  [ ] [] [ ] [ ] [ 1] [ ] 1 x x n y n x n n =  + = − + − =−  y[n −1] n −1, − n −1