A new method of realization of digital filters

A method is presented for the realization of high-performance digital filters based on the simulation of analog LC passive ladder filters (reference filters). The resulting filters can be made canonic with respect to the number of delay elements and require a reduced number of adders when compared to other equivalent realizations. The digital filters require one multiplication for each component of the reference filter, excluding the source resistor, and a one-to-one correspondence between coefficient roundoff and deviations of component values in the reference filter can be imposed. By the application of the method described, three digital filters are obtained: a second-order general filter (lowpass, bandpass, highpass) requiring two multipliers and two fifth-order lowpass filters (polynomial and elliptic)