demodulation3.m

一个基于8发1收的多天线系统的准正交差分调制例程

function y=demodulation3(x)
%DEMODULATION Summary of this function goes here
%  Detailed explanation goes here
for i=1:4;
    c1(i)=exp(j*(pi*(i-1)/2));
    c2(i)=exp(j*(pi*(i-1)/2+pi/4));
end;
i=1;
    for k=1:4;
        for n=1:4;
r(i)=abs(c1(k)+c2(n))^2*(abs(x(2,1))^2+abs(x(2,2))^2+abs(x(2,3))^2+abs(x(2,4)^2))/x(5,1)+abs(c1(k)-c2(n))^2*(abs(x(4,1))^2+abs(x(4,2))^2+abs(x(4,3))^2+abs(x(4,4))^2)/x(5,2)-2*real((ctranspose(x(1,1))*x(2,4)-x(1,2)*ctranspose(x(2,3))+x(2,2)*ctranspose(x(1,3))-x(1,4)*ctranspose(x(2,1)))*(c1(k)+c2(n))+(ctranspose(x(3,1))*x(4,4)-x(3,2)*ctranspose(x(4,3))+x(4,2)*ctranspose(x(3,3))-x(3,4)*ctranspose(x(4,1)))*(c1(k)-c2(n)));
i=i+1;
end;
end;
[m,n1]=min(r);
p=mod(n1,4);
if p==0
 p=4;
end; 
q=(n1-p)/4;
q=q+1;
y1=c1(q);
y2=c2(p);
y=cat(2,y1,y2);
y=transpose(y);