A structural design for digital filters

In this paper an approach to the design of nondistorting finite-memory digital filters is presented. The filter is considered as a multibranch system where each branch contains an extractor to select a particular input component, a functional operator to perform the desired operation (prediction, differentiation, smoothing, etc.) and an annihilator to enhance the noise rejection characteristics of the branch. Thus exact differentiation or prediction can be obtained with a considerable noise rejection figure. The complete removal of some undesirable components is also achieved. Design expressions for extractors, functional operators and annihilators are given and several applications relating mainly to computer-control systems are treated.