A New Feedback Configuration for Canonical Realization of IIR Filters and its Application to Lattice Realizations
Spandan Roy, Phani Bhushan Tholeti · IETE Journal of Research · 2008
A feedback configuration is presented for canonical realization of an arbitrary IIR transfer function H(z) = P(z) / Q(z) with M = P(z)0 < N = Q(z)0, which does not appear to have been discussed in the literature. It consists of an IIR transfer function F(z) of degree R in the forward path, where M ≤ R < N, and an FIR transfer function G(z) of degree N – M, In which the first R − M + 1 terms are absent in the feedback path. F(z) and G(z) can be realized by any structure including lattice, if applicable. Application of this method is shown to solve the problem of canonical lattice realization of any IIR transfer function H(z) = P(z) / Q(z) in which M < N and the constant term in P(z) is absent.