Effect of coefficient Quantization on the frequency response of an iir digital filter by using software

Abstract

In the realization of IIR filters in hardware or in software on general purpose computer, the accuracy with which filter, coefficients can be specified is limited by the word length of the computer or the length of the register provided to store the coefficients. In this paper, we discussed the effects of Finite word length on the performance of digital filters and how minimizing these effects. IIR filter can be realized in a direct form, a cascade form and in a parallel form. To minimize the effect of coefficient quantization, a higher-order transfer function should never be realized as a single direct form structure, but realized as a cascade or parallel of second-order and first-order sections. Using MATLAB package software programs are developed for Analysis of coefficient Quantization effects in IIR digital filter and good results are obtained.