DESIGN OF ALLPASS FILTERSWITH SPECIFIED DEGREES OF FLATNESS AND EQUIRIPPLE PHASE RESPONSES

Xi Zhang

Abstract

This paper proposes a new method for designing allpass filters having the specified degrees of flatness at the specified frequency point(s) and equiripple phase responses in the approximation band(s). First, a system of linear equations are derived from the flatness conditions. Then, the Remez exchange algorithm is used to approximate the equiripple phase responses in the approximation band(s). By incorporating the linear equations from the flatness conditions into the equiripple approximation, the design problem is formulated as a generalized eigenvalue problem. Therefore, we can solve the eigenvalue problem to obtain the filter coefficients, which have the equiripple phase response and satisfy the specified degrees of flatness simultaneously. Furthermore, a class of IIR filters composed of allpass filters are introduced as one of its applications, and it is shown that IIR filters with flat passband (or stopband) and equiripple stopband (or passband) can be designed by using the proposed method. Finally, some examples are presented to demonstrate the effectiveness of the proposed design method.

References

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Paper Citation


in Harvard Style

Zhang X. (2010). DESIGN OF ALLPASS FILTERSWITH SPECIFIED DEGREES OF FLATNESS AND EQUIRIPPLE PHASE RESPONSES . In Proceedings of the International Conference on Signal Processing and Multimedia Applications - Volume 1: SIGMAP, (ICETE 2010) ISBN 978-989-8425-19-5, pages 205-210. DOI: 10.5220/0002934102050210


in Bibtex Style

@conference{sigmap10,
author={Xi Zhang},
title={DESIGN OF ALLPASS FILTERSWITH SPECIFIED DEGREES OF FLATNESS AND EQUIRIPPLE PHASE RESPONSES},
booktitle={Proceedings of the International Conference on Signal Processing and Multimedia Applications - Volume 1: SIGMAP, (ICETE 2010)},
year={2010},
pages={205-210},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0002934102050210},
isbn={978-989-8425-19-5},
}


in EndNote Style

TY - CONF
JO - Proceedings of the International Conference on Signal Processing and Multimedia Applications - Volume 1: SIGMAP, (ICETE 2010)
TI - DESIGN OF ALLPASS FILTERSWITH SPECIFIED DEGREES OF FLATNESS AND EQUIRIPPLE PHASE RESPONSES
SN - 978-989-8425-19-5
AU - Zhang X.
PY - 2010
SP - 205
EP - 210
DO - 10.5220/0002934102050210