The Experts below are selected from a list of 255 Experts worldwide ranked by ideXlab platform

Chiencheng Tseng - One of the best experts on this subject based on the ideXlab platform.

  • design of stable iir digital filter based on least p power error criterion
    IEEE Transactions on Circuits and Systems, 2004
    Co-Authors: Chiencheng Tseng
    Abstract:

    In this paper, the least p-power error criterion is presented to design digital infinite impulse response (IIR) filters to have an arbitrarily prescribed frequency response. First, an iterative quadratic programming (QP) method is used to design a stable unconstrained one-dimensional IIR filter whose optimal filter coefficients are obtained by solving the QP problem in each iteration. Then, the proposed method is extended to design constrained IIR filters and two-dimensional IIR filters with a separable Denominator Polynomial. Finally, design examples of the low-pass filter are demonstrated to illustrate the effectiveness of the proposed iterative QP method.

  • Stable IIR notch filter design with optimal pole placement
    IEEE Transactions on Signal Processing, 2001
    Co-Authors: Chiencheng Tseng
    Abstract:

    This paper presents a two-stage approach for designing an infinite impulse response (IIR) notch filter. First, the numerator of the transfer function of the IIR notch filter is obtained by placing the zeros at the prescribed notch frequencies. Then, the Denominator Polynomial is determined by using an iterative scheme in which the optimal pole placements are found by solving a standard quadratic programming problem. For stability, the pole radius in the single notch filter design is specified by the designer, and in the multiple notch filter design, the pole radius is constrained by using the implications of Rouche's theorem. Examples are included to illustrate the effectiveness of the proposed techniques.

  • a weighted least squares method for the design of stable 1 d and 2 d iir digital filters
    IEEE Transactions on Signal Processing, 1998
    Co-Authors: Wusheng Lu, Soo-chang Pei, Chiencheng Tseng
    Abstract:

    We present a new approach to the least-squares design of stable infinite impulse response (IIR) digital filters. The design is accomplished by using an iterative scheme in which the Denominator Polynomial obtained from the preceding iteration is treated as a part of the weighting function, and each iteration is carried out by solving a standard quadratic programming problem that yields a stable rational function. When the iteration converges, a stable and truly least-squares solution is obtained. The method is then extended to address the least-squares design of stable IIR two-dimensional (2-D) filters. Examples are included to illustrate the proposed design techniques.

Balazs Bank - One of the best experts on this subject based on the ideXlab platform.

Christian Gargour - One of the best experts on this subject based on the ideXlab platform.

  • Generation of a class of two-dimensional (2-D) transfer functions yielding variable magnitude and contour characteristics
    ISCAS 2001. The 2001 IEEE International Symposium on Circuits and Systems (Cat. No.01CH37196), 2001
    Co-Authors: Christian Gargour, V. Ramachandran, R.p. Ramachandran
    Abstract:

    The properties of a two-dimensional (2-D) discrete transfer function with the degree of each variable being unity are discussed. The coefficients of the Denominator Polynomial contain a parameter k (having real values) whose bounds are determined by stability considerations. These bounds are obtained by testing the overall Polynomial at only four points z/sub 1/=/spl plusmn/1 and z/sub 2/=/spl plusmn/1. A suitable numerator Polynomial can be associated to get the overall transfer function. By varying the values of k, different magnitude and contour characteristics are obtained. Such structures can be cascaded so that the magnitude responses can be varied.

  • ISCAS (2) - Some properties of the z-domain continued fraction expansions of 1-D discrete reactance functions
    ISCAS 2001. The 2001 IEEE International Symposium on Circuits and Systems (Cat. No.01CH37196), 1
    Co-Authors: V. Ramachandran, Ravi P. Ramachandran, Christian Gargour
    Abstract:

    The Denominator Polynomial of a given causal stable z-domain transfer function is modified so that the magnitude of the frequency response remains the same. This simple modification permits an infinite number of decompositions of the modified Denominator into a mirror-image Polynomial (MIP) and an anti-mirror-image Polynomial (AMIP). Two types of Discrete Reactance Functions (DRF) are constructed. From these DRFs, continued fraction expansions (CFE) are considered and some properties are obtained. These properties indicate whether the original Denominator Polynomial has all its roots within the unit circle (is minimum phase) or not.

  • ISCAS (2) - Generation of a class of two-dimensional (2-D) transfer functions yielding variable magnitude and contour characteristics
    ISCAS 2001. The 2001 IEEE International Symposium on Circuits and Systems (Cat. No.01CH37196), 1
    Co-Authors: Christian Gargour, V. Ramachandran, Ravi P. Ramachandran
    Abstract:

    The properties of a two-dimensional (2-D) discrete transfer function with the degree of each variable being unity are discussed. The coefficients of the Denominator Polynomial contain a parameter k (having real values) whose bounds are determined by stability considerations. These bounds are obtained by testing the overall Polynomial at only four points z/sub 1/=/spl plusmn/1 and z/sub 2/=/spl plusmn/1. A suitable numerator Polynomial can be associated to get the overall transfer function. By varying the values of k, different magnitude and contour characteristics are obtained. Such structures can be cascaded so that the magnitude responses can be varied.

V. Ramachandran - One of the best experts on this subject based on the ideXlab platform.

  • Generation of a class of two-dimensional (2-D) transfer functions yielding variable magnitude and contour characteristics
    ISCAS 2001. The 2001 IEEE International Symposium on Circuits and Systems (Cat. No.01CH37196), 2001
    Co-Authors: Christian Gargour, V. Ramachandran, R.p. Ramachandran
    Abstract:

    The properties of a two-dimensional (2-D) discrete transfer function with the degree of each variable being unity are discussed. The coefficients of the Denominator Polynomial contain a parameter k (having real values) whose bounds are determined by stability considerations. These bounds are obtained by testing the overall Polynomial at only four points z/sub 1/=/spl plusmn/1 and z/sub 2/=/spl plusmn/1. A suitable numerator Polynomial can be associated to get the overall transfer function. By varying the values of k, different magnitude and contour characteristics are obtained. Such structures can be cascaded so that the magnitude responses can be varied.

  • ISCAS (2) - Some properties of the z-domain continued fraction expansions of 1-D discrete reactance functions
    ISCAS 2001. The 2001 IEEE International Symposium on Circuits and Systems (Cat. No.01CH37196), 1
    Co-Authors: V. Ramachandran, Ravi P. Ramachandran, Christian Gargour
    Abstract:

    The Denominator Polynomial of a given causal stable z-domain transfer function is modified so that the magnitude of the frequency response remains the same. This simple modification permits an infinite number of decompositions of the modified Denominator into a mirror-image Polynomial (MIP) and an anti-mirror-image Polynomial (AMIP). Two types of Discrete Reactance Functions (DRF) are constructed. From these DRFs, continued fraction expansions (CFE) are considered and some properties are obtained. These properties indicate whether the original Denominator Polynomial has all its roots within the unit circle (is minimum phase) or not.

  • ISCAS (2) - Generation of a class of two-dimensional (2-D) transfer functions yielding variable magnitude and contour characteristics
    ISCAS 2001. The 2001 IEEE International Symposium on Circuits and Systems (Cat. No.01CH37196), 1
    Co-Authors: Christian Gargour, V. Ramachandran, Ravi P. Ramachandran
    Abstract:

    The properties of a two-dimensional (2-D) discrete transfer function with the degree of each variable being unity are discussed. The coefficients of the Denominator Polynomial contain a parameter k (having real values) whose bounds are determined by stability considerations. These bounds are obtained by testing the overall Polynomial at only four points z/sub 1/=/spl plusmn/1 and z/sub 2/=/spl plusmn/1. A suitable numerator Polynomial can be associated to get the overall transfer function. By varying the values of k, different magnitude and contour characteristics are obtained. Such structures can be cascaded so that the magnitude responses can be varied.

R.p. Ramachandran - One of the best experts on this subject based on the ideXlab platform.

  • Generation of a class of two-dimensional (2-D) transfer functions yielding variable magnitude and contour characteristics
    ISCAS 2001. The 2001 IEEE International Symposium on Circuits and Systems (Cat. No.01CH37196), 2001
    Co-Authors: Christian Gargour, V. Ramachandran, R.p. Ramachandran
    Abstract:

    The properties of a two-dimensional (2-D) discrete transfer function with the degree of each variable being unity are discussed. The coefficients of the Denominator Polynomial contain a parameter k (having real values) whose bounds are determined by stability considerations. These bounds are obtained by testing the overall Polynomial at only four points z/sub 1/=/spl plusmn/1 and z/sub 2/=/spl plusmn/1. A suitable numerator Polynomial can be associated to get the overall transfer function. By varying the values of k, different magnitude and contour characteristics are obtained. Such structures can be cascaded so that the magnitude responses can be varied.

  • A fast algorithm for finding the adaptive component weighted cepstrum for speaker recognition
    IEEE Transactions on Speech and Audio Processing, 1997
    Co-Authors: R.p. Ramachandran, R.j. Mammone
    Abstract:

    In speaker recognition systems, the adaptive component weighted (ACW) cepstrum has been shown to be more robust than the conventional linear predictive (LP) cepstrum. The ACW cepstrum is derived from a pole-zero transfer function whose Denominator is the pth-order LP Polynomial A(z). The numerator is a (p-1)th-order Polynomial that is up to now found as follows. The roots of A(z) are computed, and the corresponding residues obtained by a partial fraction expansion of 1/A(z) are set to unity. Therefore, the numerator is the sum of all the (p-1)th-order cofactors of A(z). We show that the numerator Polynomial is merely the derivative of the Denominator Polynomial A(z). This greatly speeds up the computation of the numerator Polynomial coefficients since it involves a simple scaling of the Denominator Polynomial coefficients. Root finding is completely eliminated. Since the Denominator is guaranteed to be minimum phase and the numerator can be proven to be minimum phase, two separate recursions involving the Polynomial coefficients establishes the ACW cepstrum. This new method, which avoids root finding, reduces the computer time significantly and imposes negligible overhead when compared with the approach of finding the LP cepstrum.