qr_mmse_decode.m

程序是MIMO-OFDM系统下

function output=QR_MMSE_decode(Y,H,Cons,No)
len=size(H);
ch=H;
G=inv(H'*H+No*eye(len(2)))*H';
S=zeros(1,len(2));
for i=1:1:len(2)
    len1=size(G,1);
    for l=1:1:len1
        m(l)=norm(G(l,:));
    end    
    n=find(m==min(m));
    m=zeros(1,len(2)-i);
    know=1;
    kpre=n;
  while(kpre>=know)
     if S(1,know)~=0
        kpre=kpre+1;
     end
     know=know+1;
  end
  S(kpre)=kpre;
  w=G(n,:);
  y=w*Y;
  for k=1:1:4
      M(k)=(y-Cons(k))*conj(y-Cons(k));
  end
  output(kpre,:)=Cons(find(M==min(M)));
  Y=Y-output(kpre,:)*H(:,kpre);
  h=zeros(len(1),len(2)-i);
  h=ch(:,[1:n-1,n+1:len(2)-i+1]);
  ch=h;
  b=size(ch,2);
  G=inv(ch'*ch+(No)*eye(b))*ch';
end