Poles and Zeros

Laplace / Continuous Time

• $H(s)$ has a pole at $s=a$ if $|H(a)|=\infty$
• $H(s)$ has a zero at $s=a$ if $|H(a)|=0$

Z-transform / Discrete Time

• $H[z]$ has a pole at $z=a$ if $|H(a)|=\infty$
• $H[z]$ has a zero at $s=a$ if $|H[a]|=0$

Poles: $x$ Zeros: $0$