www.pudn.com > voicebox2.zip > LPCBWEXP.M

function arx=lpcbwexp(ar,bw) 
%LPCBWEXP expand formant bandwidths of LPC filter ARX=(AR,BW) 
%minimum bandwidth will be BW*fs where fs is the sampling frequency 
%the radius of each pole will be multiplied by R=exp(-BW*pi) 
% To set the maximum pole radius to R use BW=-log(R)/PI. 
 
 
 
%      Copyright (C) Mike Brookes 1998 
% 
%      Last modified Sun Jan  2 20:12:38 2000 
% 
%   VOICEBOX is a MATLAB toolbox for speech processing. Home page is at 
%   http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/voicebox.html 
% 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
%   This program is free software; you can redistribute it and/or modify 
%   it under the terms of the GNU General Public License as published by 
%   the Free Software Foundation; either version 2 of the License, or 
%   (at your option) any later version. 
% 
%   This program is distributed in the hope that it will be useful, 
%   but WITHOUT ANY WARRANTY; without even the implied warranty of 
%   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
%   GNU General Public License for more details. 
% 
%   You can obtain a copy of the GNU General Public License from 
%   ftp://prep.ai.mit.edu/pub/gnu/COPYING-2.0 or by writing to 
%   Free Software Foundation, Inc.,675 Mass Ave, Cambridge, MA 02139, USA. 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
 
[nf,p1]=size(ar); 
k=exp(-pi*(0:p1-1)*bw); 
arx=ar.*k(ones(nf,1),:);