arcma.m

基于Matlab

%arcma
%cma for ar realization

clear

ii=sqrt(-1);

channo=input('channel number (1 or 2) = ');
if channo<1.5 
croots=[.6,.5+.1*ii,.5-.1*ii];  %works with both algorithms
else
croots=[.8,.7+.3*ii,.7-.3*ii]; %problems with Feintuch variant
				%works with CM-minimizing variant
end

c=real(poly(croots));
lc=length(c);

nits=input('number of iterations = ');

x=sign(rand(1,nits+lc)-0.5*ones(1,nits+lc));
r=zeros(1,nits);

for ind=1:nits
r(ind)=c*x(ind+lc-1:-1:ind)';
end

lb=lc-1;
initfac=input('initialization factor (between -1 and 1) of desired value = ');
b=zeros(nits,lb);
b(1,:)=initfac*(-c(2:lc));

rootb=zeros(nits,lb);
rootb(1,:)=roots([1 -b(1,:)])';

y=zeros(1,nits+lb-1);
yf=zeros(1,nits+lb-1);

mu=input('stepsize (e.g. 0.0002) = ');

algchoice=input('algorithm number (Feintuch=1, CM-minimizing=2) = ');

for ind=1:nits-1
y(ind+lb)=r(ind)+b(ind,:)*y(ind+lb-1:-1:ind)';

if algchoice <1.5
%Feintuch variant
b(ind+1,:)=b(ind,:)+mu*y(ind+lb-1:-1:ind)*y(ind+lb)*(1-y(ind+lb)*y(ind+lb));
else
%CM-minimizing variant with regressor filtering
yf(ind+lb)=y(ind+lb)+b(ind,:)*yf(ind+lb-1:-1:ind)';
b(ind+1,:)=b(ind,:)+mu*yf(ind+lb-1:-1:ind)*y(ind+lb)*(1-y(ind+lb)*y(ind+lb));

rootb(ind+1,:)=roots([1 -b(ind+1,:)])';

end
end

final_parameter_error=-c(2:lc)-b(nits,:)

figure(1)
plot(y.*y)
title('squared equalizer output - should be 1')

figure(2)
plot(b)
hold on
plot(ones(nits,1)*(-c(2:lc)),':')
hold off
title('parameter trajectories')

%to insure plot of complex roots a small imaginary part is added
%to all root locations prior to plotting
figure(3)
plot(rootb+0.000001*ii*ones(size(rootb)),'+k')
hold on
plot(rootb(1,:)+0.000001*ii*ones(size(rootb(1,:))),'or')
plot(rootb(nits,:)+0.000001*ii*ones(size(rootb(nits,:))),'dg')
plot(roots(c)+0.000001*ii*ones(size(roots(c))),'*m')
hold off
title('adapting root locations (o:start, diamond:end, *:desired)')