rec_fromphase_part.m

基于二发二收MIMO系统的半盲信道估计

function [look2,ls_error]=rec_fromphase_part(theta2,NF,N,Index,look_true)

ls_error=[];
slopes=[];

N0=theta2(NF/2+1)/pi;

nloop=1;
check=100;

for nn=-N:N
   
   Phi1=zeros(1,length(Index));   
   phi1=zeros(1,length(Index));
   
   psi1=theta2+2*pi/NF*[0:NF-1]*nn;
   tmp=psi1;
   psi1=reshape(psi1,NF,1);
   
   if (abs(check) > 0. )
      Lpos=N-1;
      vec1=[1:Lpos];
      
      pies1=(2*pi/NF)*[0:NF-1]'*vec1;
      for jj=1:length(vec1)
         ang1(Index,jj)=psi1(Index);
      end
      
      Phi1=sin(pies1(Index,:)+ang1(Index,:));  phi1=-sin(psi1(Index));
      
      look2=inv((Phi1)'*Phi1)*(Phi1)'*phi1;
      
      look2=[1 look2(1:Lpos)'];
      [lk,ll]=max(abs(look2));
      look2=look2/look2(ll);
      
      rec=look2;
      
      LOOK=fft(look2,NF);
      
      RE=fft(rec,NF);
      check=mean((detrend(phase(RE))-detrend(theta2)).^2);
      
      ls_error=[ls_error log10(check)];
      REC(nloop,:)=rec;
      NN(nloop)=nn;
      nloop=nloop+1;
   end
   
   look2=rec;
end

[lsm, ls_index]=min(ls_error);

look2=REC(ls_index,:);
shift=NN(ls_index);