A Unified Approach for Realization of IIR Filters in Delta Domain

Abstract

In this paper, digital realization of IIR filters is concentrated in discrete delta domain.Whenever, a continuous time filter is discretised at fast sampling rate, corresponding discrete time filter in conventional z-domain realization fails to provide meaningful information. In other way, the delta domain based system provides the continuous time results at fast sampling rate leading to the development of a unified method for filter realization in digital domain. Realization of the digital filter using delta operator is having very good finite word length performance under high sampling rate. Three different types of IIR filters are considered for the digital realization in delta domain. The transposed delta direct form II (DDFT-II) structure is used to realize the filters, as it is the most suitable structure for digital filter realization. Butterworth, Chebyshev -2 and Elliptic filters are considered as example and Matlab Simulink is used to realize the digital filter in delta domain .The frequency response analysis proves the efficacy of the proposed method.