A New Design for Linear Phase IIR Digital Filter with Efficient Realization

Abstract

Abstract:Linear phase requirement can be achieved by direct design with an FIR filter atthe expense of high order and high computational burden for the given specification.Alternatively, IIR digital filters can be designed with much smaller order than their FIRcounterparts, but at the expense of the non-linear phase. In this paper, a new design oflinear phase IIR digital filter is presented by composing a zero phase efficientlydesigned FIR digital filter with maximally flat group delay. The new IIR digital filter isdesigned with a lower order satisfying the same roll-off magnitude response of thecorresponding FIR filter and preserving the approximate pass-band characteristics.