Causality Condition of a Discrete-Time LTI System Example- The discrete-time accumulator defined by yn=∑门 C=-∞ is a causal system as it has a causal impulse response given by hn]=∑8]=m] l= Copyright C 2001, S.K. MitraCopyright © 2001, S. K. Mitra 11 Causality Condition of a Discrete-Time LTI System • Example - The discrete-time accumulator defined by is a causal system as it has a causal impulse response given by [ ] [ ] n y n x =− =  h[n] [ ] [n] n =  =  =− 