Coefficient Reduction Method for Stopband Ripple Minimization of IFIR Filter

Abstract

This paper presents a technique for minimization of ripples of interpolated finite impulse response (IFIR) filter. Single-stage and two-stage IFIR filters are designed using the Remez exchange algorithm. The performance of these filters is improved by minimizing the ripples in the stopband region by discarding zero-valued coefficients. The proposed technique yields the desired filter response of IFIR filters matching closely with the required response of finite impulse response (FIR) filter in the passband and stopband regions, providing very low computational complexity and sharp transition width as compared to the conventional FIR filter. In comparison to other existing techniques, the proposed algorithm reduces the stopband ripples significantly (the distortion in the frequency domain is reduced up to 61.20%). As a result, the power losses in the filtered signal are reduced, thereby enhancing the sensitivity and its consistency during the filtering process.

KEYWORDS:

• Computational complexity reduction
• IFIR filter
• Narrow band filter
• Sharp transition width
• Stopband ripples

Additional information

Notes on contributors

S. Chandra

Shanti Chandra received her BTech degree in electronics and instrumentation engineering from the MJP Rohelkhand University, Bareilly, Utter Pradesh, India, in 2010 and an MTech degree in electronics and communications from Indian Institute of Information Technology, Madhya Pradesh, India, in 2014. She is currently a PhD scholar in the Department of Electrical, Indian Institute of Technology, Roorkee, India. Her research interests are in signal processing, biological signal processing and pattern recognition.

A. Sharma

Ambalika Sharma received a BE degree in electronics and communication engineering from Indian Institute of Technology, Roorkee, India, an MTech degree in electrical engineering from the Indian Institute of Technology, Roorkee, India and a PhD degree from Annamalai University, India. Currently, she is an assistant professor in the Department of Electrical Engineering at Indian Institute of Technology, Roorkee, India. Her research interests are in biomedical engineering, signal processing, AI, wavelet and multirate signal processing, ECG signal analysis and heart rate variability. Email: [email protected]

G. K. Singh

Girish Kumar Singh received the BTech degree from G B Pant University of Agriculture and Technology, Pantnagar, India, in 1981, and the PhD degree from Banaras Hindu University, Varanasi, India, in 1991, both in electrical engineering. He worked in industry for nearly five and a half years. In 1991, he joined MNR Engineering College, Allahabad, India, as a lecturer. In 1996, he moved to the University of Roorkee, Roorkee, India. Currently, he is a professor in the Electrical Engineering Department, Indian Institute of Technology, Roorkee, India. He has been involved in design and analysis of electrical machines in general and high-phase-order AC machines in particular and power system harmonics and power quality. He has coordinated a number of research projects sponsored by the CSIR and UGC, Government of India. He has served as a Visiting Associate Professor in the Department of Electrical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Korea, and as visiting professor in the Department of Electrical and Electronics Engineering, Middle East Technical University, Ankara, Turkey. Prof Singh received the Pt Madan Mohan Malaviya Memorial Medal and the Certificate of Merit Award 2001–2002 of the Institution of Engineers (India). Email: [email protected]