Topics in Signal Processing pp 323-330 | Cite as

# A New Feedback Configuration for Canonical Realization of IIR Filters and Its Application to Lattice Realizations

## Abstract

A feedback configuration is presented for canonical realization of an arbitrary IIR transfer function *H*(*z*) = *P*(*z*)/*Q*(*z*) with \( M = P\left( z \right)^{0} < N = Q\left( z \right)^{0} \), 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.

## Keywords

IIR filters Feedback configuration Canonical realization Lattice structures## Notes

### Acknowledgements

After the publication of [2], it was pointed out by Professor S. K. Mitra of the University of California, Santa Barbara, that the idea of using two different parameters in a lattice section was exploited earlier in [4]. However, the approach, algorithms and the final realizations are, in general, different.

## References

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