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Update ltpda_uo.fromRepository
author
Daniele Nicolodi <nicolodi@science.unitn.it>
date
Mon, 05 Dec 2011 16:20:06 +0100 (2011-12-05)
parents
f0afece42f48
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+ − % PFALLPS2 all pass filtering to stabilize TF poles and zeros.
+ − %
+ − %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+ − % DESCRIPTION:
+ − %
+ − % All pass filtering in order to stabilize transfer function poles and
+ − % zeros. It inputs a partial fraction expanded discrete model and
+ − % outputs a pole-zero minimum phase system
+ − %
+ − % CALL:
+ − %
+ − % [resp,np] = pfallps2(ip,mresp,f)
+ − %
+ − % INPUTS:
+ − %
+ − % ip: are poles
+ − % f: is the frequancies vector in (Hz)
+ − % fs: is the sampling frequency in (Hz)
+ − %
+ − % OUTPUTS:
+ − %
+ − % resp: is the functions phase frequency response
+ − % np: are the new stable poles
+ − %
+ − % NOTE:
+ − %
+ − %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+ − % VERSION: $Id: pfallpz.m,v 1.6 2009/06/10 15:47:00 luigi Exp $
+ − %
+ − % HISTORY: 12-09-2008 L Ferraioli
+ − % Creation
+ − %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+ − function varargout = pfallps2(ip,mresp,f)
+ −
+ − [a,b] = size(ip);
+ − if a<b
+ − ip = ip.'; % reshape as a column vector
+ − end
+ −
+ − [a,b] = size(f);
+ − if a<b
+ − f = f.'; % reshape as a column vector
+ − end
+ −
+ − %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+ −
+ − Nb = numel(ip);
+ − for nn = 1:Nb
+ −
+ − p = ip(nn).poles;
+ −
+ − % stabilizing poles
+ − sp = p;
+ − unst = real(p) > 0;
+ −
+ − sp(unst) = conj(sp(unst));
+ −
+ −
+ −
+ − pp = p(unst);
+ − psp = sp(unst);
+ − allpstr = '(1';
+ − for jj = 1:numel(sp(unst))
+ − allpstr = [allpstr sprintf('.*((s-%0.20d)./(s+%0.20d))',pp(jj),psp(jj))];
+ − end
+ − allpstr = [allpstr ')'];
+ −
+ − funcell{nn} = allpstr;
+ −
+ − end
+ −
+ −
+ − s = (1i*2*pi).*f;
+ − fullallprsp = 1;
+ −
+ − for nn = 1:Nb
+ −
+ − nterm = eval(funcell{nn});
+ − % willing to work with columns
+ − if size(nterm,2)>1
+ − nterm = nterm.';
+ − end
+ −
+ − allprsp(:,nn) = nterm;
+ −
+ − fullallprsp = fullallprsp.*nterm;
+ −
+ − end
+ −
+ − phs = angle(fullallprsp);
+ −
+ − for kk=1:Nb
+ − resp(:,kk) = mresp(:,kk).*(cos(phs)+1i.*sin(phs));
+ − end
+ −
+ −
+ − % output
+ − if nargout == 1
+ − varargout{1} = resp;
+ − else
+ − error('Too many output arguments!')
+ − end
+ − end
+ −
+ −
+ −
+ −