An efficient local search method guided by gradient information for discrete coefficient FIR filter design

2002-10-01
Çiloğlu, Tolga
A new local search method for the design of linear phase FIR filters with discrete valued coefficients is introduced in this paper. Conventional minimax criterion and normalized peak ripple magnitude (NPRM) are taken as objective functions. The principle is to search along low gradient routes with priority and to direct the search toward steeper sides as improved solutions cease to appear. The characteristics of the objective functions have been explained and used to devise the method. The method is novel in the way it generates the gradient information and makes use of it. At each step, a number of filter coefficients are picked according to the gradient information and perturbed to look for improved solutions. A specific neighborhood definition is proposed and used in perturbing the coefficients. The method has very low computational demand and is suitable for the design of long filters. The results of design examples demonstrate that the performance of the method can compete with those of optimal methods. Along the way, a closed form expression for the "filter gain" that minimizes NPRM is also given. Furthermore, it is shown that a previously proposed local search method unintentionally implements the ideas of this paper in an opposite order.
SIGNAL PROCESSING

Suggestions

A NOVEL METHOD FOR DISCRETE COEFFICIENT FIR DIGITAL FILTER DESIGN
Çiloğlu, Tolga (1994-06-02)
A local search algorithm for discrete coefficient FIR filter design is presented. The minmax objective function is minimized by moving along the low gradient directions. A new method to forecast these directions is proposed. The algorithm is suitable to design high order filters in a short time. The results are compared to other methods both in quality and computational load
A Simple Method to Design Ridge Waveguide Filters with Evanescent Mode Couplings
Ozturk, Onur Ozan; Yıldırım, Nevzat (2022-01-01)
A simple approach is introduced to design ridge waveguide (RWG) filters with evanescent waveguide (EWG) couplings based on the observation that when all inverters and all resonators of an inverter coupled filter are replaced by equal length EWG pieces and equal length RWG pieces respectively, all responses are destroyed (bandwidth changes, passband shifts away and passband ripple increases) but the number of reflection zeros are preserved. It is noticed that the targeted responses of this highly distorted f...
The DRBEM solution of incompressible MHD flow equations
Bozkaya, Nuray; Tezer, Münevver (Wiley, 2011-12-10)
This paper presents a dual reciprocity boundary element method (DRBEM) formulation coupled with an implicit backward difference time integration scheme for the solution of the incompressible magnetohydrodynamic (MHD) flow equations. The governing equations are the coupled system of Navier-Stokes equations and Maxwell's equations of electromagnetics through Ohm's law. We are concerned with a stream function-vorticity-magnetic induction-current density formulation of the full MHD equations in 2D. The stream f...
Analysis of root displacement interpolation method for tunable allpass fractional-delay filters
Hacıhabiboğlu, Hüseyin; Günel Kılıç, Banu (2007-10-01)
One of the simplest ways of designing allpass fractional-delay filters with maximally fiat group delays is by using the Thiran approximation by which the filter coefficients are calculated using a closed-form equation. However, due to the number of multiplications and divisions involved, the calculation of these coefficients is a computationally costly task and is not suitable for real-time applications. The analysis of a root-displacement-based interpolation method used in allpass tunable fractional delays...
An adaptive fully discontinuous Galerkin level set method for incompressible multiphase flows
KARAKUS, Ali; WARBURTON, Tim; AKSEL, MEHMET HALUK; Sert, Cüneyt (Emerald, 2018-01-01)
Purpose This study aims to focus on the development of a high-order discontinuous Galerkin method for the solution of unsteady, incompressible, multiphase flows with level set interface formulation.
Citation Formats
T. Çiloğlu, “An efficient local search method guided by gradient information for discrete coefficient FIR filter design,” SIGNAL PROCESSING, pp. 1337–1350, 2002, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/33281.