A Novel Methodology for Designing Linear Phase IIR Filters

Abstract—This paper presents a novel technique for designing an Infinite Impulse Response (IIR) Filter with Linear Phase Response. The design of IIR filter is always a challenging task due to the reason that a Linear Phase Response is not realizable in this kind. The conventional techniques involve large number of samples and higher order filter for better approximation resulting in complex hardware for implementing the same. In addition, an extensive computational resource for obtaining the inverse of huge matrices is required. However, we propose a technique, which uses the frequency domain sampling along with the linear programming concept to achieve a filter design, which gives a best approximation for the linear phase response. The proposed method can give the closest response with less number of samples (only 10) and is computationally simple. We have presented the filter design along with its formulation and solving methodology. Numerical results are used to substantiate the efficiency of the proposed method. Index Terms—Infinite impulse response, linear programming, filter design, linear phase filters I