A comparative study of two classes of efficient lattice filters with structure robustness consideration

This paper deals with low complexity digital filter structures with consideration of maximizing a newly defined structure robustness measure. Two classes of efficient lattice-based filter structures are considered. For an Nth order digital filter, the structures in these classes all have 2N + 1 multipliers. The expression of robustness measure is derived and the optimum structure problem is formulated in terms of maximizing this measure with respect to the degrees of freedom for each of the two classes. A design example is presented to demonstrate the excellent finite wordlength performance of the optimized structures.