Performance analysis of a new structure for digital filter implementation

It is well known that for a digital filter of order n the number of nontriv ial parameters in the classical optimal state-space realizations is proport ional to n(2). In this paper, a new structure is proposed for digital filte r implementation. This structure possesses 5n - 1 nontrivial parameters and is shown to be equivalent to the discrete-time counterpart of the well-kno wn orthonormal ladder filter in [13], A new property of this ladder filter is revealed. The performance of the proposed structure is analyzed. Express ions for evaluating the sensitivity measure and the roundoff noise gain are derived. A numerical example is presented to illustrate the design procedu re. Simulations show that the performance of the proposed structure is almo st the same as that of the fully parameterized optimal realizations.