Stability LTI System Stable分∑?h<∞台 RoC of h() includes the unit circle ==1 Frequency Response H(e/%)tFT of h[n)exists A causal LtI system with rational system function is stable o all poles are inside the unit circle, i.e. have magnitudes 1Stability • A causal LTI system with rational system function is stable ⇔ all poles are inside the unit circle, i.e. have magnitudes < 1 • LTI System Stable ⇔ ROC of H(z) includes the unit circle |z| = 1 ⇒ Frequency Response H(ejω) (DTFT of h[n]) exists