Design of optimal digital lattice filter structures based on genetic algorithm

In this paper, a new class of lattice-based digital filter structures is derived. The optimum structure problem is formulated in terms of minimizing the signal power ratio with respect to the two sets of free parameters in the proposed structures. An efficient genetic algorithm is proposed to solve the optimum structure problem with the constraint on the structure parameters to be represented in signed power-of-two format. Two design examples are given, in which the optimized structures show excellent finite wordlength properties such as very low parameter sensitivity and very uniform signal powers across signal nodes and outperform the classical lattice structures.

► A new digital lattice filter structure is derived.
► It has some degrees of freedom in structure parameters for optimizing the structure.
► An efficient genetic algorithm is developed for solving the optimal structure problem.
► The optimized structure has very low parameter sensitivity and signal power ratio.