quasidecode44.m

包括4天线准正交码的编码和解码程序

%decode layer by layer
function  out=decode44(H,Nr,r,n,M)
%const=[1+j,1+j*3,3+j,3+j*3,1-j,1-3*j,3-j,3-3*j,-1+j,-1+3*j,-3+j,-3+3*j,-1-j,-1-3*j,-3-j,-3-3*j];
m1=[];m2=[];m3=[];g1=[];g2=[];g3=[];out=[];F=[];
   for L=1:M
       s(L)=qammod(L-1,M);
   end
%s=genqammod(0:M-1,const);
     if n==2
     for t=1:Nr
        m1=[conj(H(t,2)),-conj(H(t,1)),conj(H(t,4)),-conj(H(t,3))];
        g1(2*t-1:2*t,:)=[H(t,:);m1];
     end
     r11=[r(:,1) conj(r(:,2))];
     r_1=reshape(r11.',[],1);
     elseif n==3
        for t=1:Nr 
        m1=[conj(H(t,2)),-conj(H(t,1)),conj(H(t,4)),-conj(H(t,3))];
        m2=[H(t,3),H(t,4),H(t,1),H(t,2)];
        g1(3*t-2:3*t,:)=[H(t,:);m1;m2];
        end
    r11=[r(:,1) conj(r(:,2)) r(:,3)];
    r_1=reshape(r11.',[],1);  
    else
         for t=1:Nr
       m1=[conj(H(t,2)),-conj(H(t,1)),conj(H(t,4)),-conj(H(t,3))];
       m2=[H(t,3),H(t,4),H(t,1),H(t,2)];
       m3=[conj(H(t,4)),-conj(H(t,3)),conj(H(t,2)),-conj(H(t,1))];
       g1(4*t-3:4*t,:)=[H(t,:);m1;m2;m3];
         end
    r11=[r(:,1) conj(r(:,2)) r(:,3) conj(r(:,4))];
    r_1=reshape(r11.',[],1);
     end
 %   out1=pinv(g1)*r_1;
%   out=genqamdemod(out1,const);
     G=g1'*g1;
     A=G(1:2,1:2);B=G(3:4,3:4);C=G(1:2,3:4);D=G(3:4,1:2);
     W=[eye(2),-C*inv(B);-D*inv(A),eye(2)];

       r1=W*g1'*r_1;
       H1=W*G;
   for i1=1:M
       F1(i1)=norm(r1(1)-H1(1,1)*s(i1));
       F2(i1)=norm(r1(2)-H1(2,2)*s(i1));
       F3(i1)=norm(r1(3)-H1(3,3)*s(i1));
       F4(i1)=norm(r1(4)-H1(4,4)*s(i1));
    end
   [v p]=min(F1);
     S1=s(p);
   [v p]=min(F2);
     S2=s(p);
   [v p]=min(F3);
     S3=s(p); 
   [v p]=min(F4);
     S4=s(p);
     out1=[S1;S2;S3;S4];
       out=qamdemod(out1,M);