A method of determining all equivalent structures of digital filters

The work describes systems of linear differential equations with constant coefficients used for digital circuitry. These equations are employed in calculations for digital filters, CCD filters, circuit-capacitor filters and equalizers. Attention is given to the use of digital filters in analog systems, to the bandwidth limitations and scanning of a digital signal, and to analog to digital conversion. The analog principle of linear circuit transformation is used to find equivalent digital circuits. It is shown that Cauer's (1954) transformation of a passive network method and Lueder's (1962) method for establishing an equivalent passive quadruple can be applied to all networks that are governed by systems of linear equations.