Estimation of structural complexity of IIR digital filters

The paper is devoted to technique of comparison of various structures of IIR digital filters on complexity taking into consideration the accuracy of implementation of characteristics. An offered technique is based on dividing of all possible structures into classes of equivalence. All structures belonging to the same equivalence class have the same position of zeros and poles in the z-plane. This location is determined by the algebraic-numerical nature of the poles and zeros of the filters with coefficients of finite word length. Each evaluated structure is assigned a reference canonical form with same zeros and poles. The concept of structural complexity considering complexity of realization of operations of multiplication in estimated and reference structures is introduced.