Low roundoff noise and normal realizations of fixed point IIR digital filters

Abstract

Explicit design and performance equations are given in terms of the parameters of the desired transfer function H(z) for two classes of realizations. These realizations offer the digital circuit designer an alternative to the usual designs based on direct forms. In addition to low roundoff noise, these new realizations offer other desirable properties such as low coefficient sensitivities and freedom from overflow oscillations. Numerical results are presented which detail the design process and verify the theory.