Search of optimal RNS IIR digital filter implementation

An approach to search an optimal realization of an IIR digital filter, applying RNS methods, working in the field of rational numbers, is presented. The approach, denoted as DMM, implements the given structure by two processors working in parallel and based on two modular integer arithmetics. Two different moduli, prime with respect to each other, are chosen. The outputs of these processors are then recombined to accounting for the quantization effects. The choice of these modules has been optimized, showing that a value of a power-of-two for one module and a composite value for the second one can minimize the chip area. This result was compared with the choice of prime modules, which is very simple from a theoretical point of view. It is shown that with an increase of only 5% in the occupied area, the dynamic range is extended by about one bit