A New Delta Operator Based IIR Lattice Filter Structure

Delta operator-based implementation over the conventional shift operator approach has been applied to the direct form based structure, and the satisfactory performance including low roundoff noise gain and low coefficient sensitivity, has been achieved. However, the approach for delta operator has not been applied into the lattice filter structure. In this paper, a novel lattice filter structure is derived based on the delta operator. The expression of roundoff noise gain for the proposed structure is derived. For an Nth order digital filter, the proposed structure requires 5N + 1 multipliers, which yields the same implementation complexity as the normalized lattice structure. A numerical example is presented to demonstrate the performance of the proposed structure.