Causality Condition of a Discrete-Time LTI System n[m]=∑k]x[-k]=∑k]x1[-k k=-∞ k=0 +∑hk]x1{m-k] k y2[no=∑hk]x2[m-k]=∑hkx2[m-k k: k=0 +∑hk]x2{o-k] Copyright C 2001, S K MitraCopyright © 2001, S. K. Mitra 7 Causality Condition of a Discrete-Time LTI System    =  =− = − = − 0 2 2 2 k o k o o y [n ] h[k]x [n k] h[k]x [n k]  − =− + − 1 2 k o h[k]x [n k]    =  =− = − = − 0 1 1 1 k o k o o y [n ] h[k]x [n k] h[k]x [n k]  − =− + − 1 1 k o h[k]x [n k]