Design of Digital Filters with Amplitude and Group Delay Specifications

Document type: Conference Papers
Peer reviewed: Yes
Author(s): Zhuquan Zang, Sven Nordholm, Sven Nordebo, Antonio Cantoni
Title: Design of Digital Filters with Amplitude and Group Delay Specifications
Conference name: 11th IEEE Signal Processing Workshop on Statistical Signal Processing
Year: 2001
Pagination: 357-60
ISBN: 0-7803-7011-2
Publisher: IEEE
City: Singapore
Organization: Blekinge Institute of Technology
Department: Department of Telecommunications and Signal Processing (Institutionen för telekommunikation och signalbehandling)
Department of Telecommunications and Signal Processing S-372 25 Ronneby
+46 455 38 50 00
Language: English
Abstract: This paper considers the design of a digital filter with prescribed magnitude and group delay specifications. First, we outline the derivation of the phase and group delay functions of an Nth order digital Laguerre filter and show that the group delay function of the filter can be written as a ratio of quadratic functions in the filter coefficients. Then, we formulate our filter design problem as a constrained L2 space minimization problem in which the performance requirement on the group delay and magnitude in the passband are treated as constraints while minimizing the L2 norm of the error function between the designed and the desired filters. Methods for solving the proposed nonlinear optimization problem axe outlined. Numerical results are presented to illustrate the usefulness of the proposed method. As a special case, corresponding results for general FIR filters axe also derived
Subject: Signal Processing\Filter Design
Keywords: delay filters, digital filters, filtering theory, FIR filters, minimisation, optimisation, digital filter design, magnitude specifications, group delay specifications, amplitude specifications, phase functions, Nth order digital Laguerre filter, quadratic functions, filter coefficients, passband, constrained L2 space minimization problem, nonlinear optimization problem, FIR filters, numerical results