afdqfmax.m

AFD - Advanced Filter Design using MATLABMiroslav D. Lutovac, Dejan V. Tosicversion 1.00 released 15

function Qmax=afdqfmax(den)

% afdqfmax.m  AFD quality factor maximum 
%             from transfer function denominator
%
% 2:32  16/2/99
%
%   Authors: Dejan V. Tosic, Miroslav D. Lutovac, 1999.02.08
%                 [e-mail]
%                 [e-mail]
%
%   Copyright (c) 1999 by Tosic & Lutovac
%   $Revision: 1.0 $  $Date: 1999/02/08 03:07:42 $
%
%   References:
%        Miroslav D. Lutovac, Dejan V. Tosic, Brian L. Evans
%           Advanced Filter Design for Signal Processing
%                   Using MATLAB and Mathematica

poles = roots(den);
qf    = -0.5*abs(poles)./real(poles);
Qmax  =  max(qf);