H(z) = \frac{Y (z)}{X(z)} = \frac{∑_{q=0}^{M} z^{−q}β_{q}}{∑_{p=0}^{N} z^{−p}α_{p}} = \frac{β_{0} + z^{−1}β_{1} + z^{−2}β_{2} + ... + z^{−M}β_{M}}{α_{0} + z^{−1}α_{1} + z^{−2}α_{2} + ... + z^{−N}α_{N}}