stbcg2_rx.m

该系统主要使用matlab实现了stbc2*1系统的发送和接收

function [Svest,Gest,shat]=stbcG2_rx(rx,H)
%This is modified version code G2.  Here the rx data has already been 
%determined.  This is b/c this routine can be run multiple times and we don't   
%want to keep genearation new random data.
%Routine that preforms simulations based on PSK Mary modulation
%and using coding scheme G2.
%G2 : |  x1   x2  |
%     | -x2*  x1* |
%rx is the received data
%H is the ESTIMATED channel matrix
%soft are 
global nTx nRx Mary Smap 

%Initialize vectory
shat = zeros(nTx,1);
soft = zeros(nTx,Mary);
    
%Demodulate
%Detecting s1 and s2, minimize decision metric
S1=0; S2=0; Hnorm=0;
for j=1:nRx,
        S1 = S1 + rx(j,1)*H(j,1)' + rx(j,2)'*H(j,2);
        
        S2 = S2 + rx(j,1)*H(j,2)' - rx(j,2)'*H(j,1);
        
        Hnorm = Hnorm + H(j,:)*H(j,:)';
end
for L=1:Mary
    Con = (-1 + Hnorm) * Smap(L) * Smap(L)';
    
    %For s1
    soft(1,L) = soft(1,L) + real( (S1 - Smap(L))*(S1 - Smap(L))' + Con);
    
    %For s2
    soft(2,L) = soft(2,L) + real( (S2 - Smap(L))*(S2 - Smap(L))' + Con);
end
%Choose symbols that minimize the est_* vectors
%Decide in favour of min value 
[A,B]=min(soft(1,:));
shat(1)=B;   
[A,B]=min(soft(2,:));
shat(2)=B;    

%Form coding matrix G from estimated symbols
%G2 : |  x1   x2  |
%     | -x2*  x1* |
[Svest]=psk_gen(Mary,shat);
Gest = [ Svest(1)  -Svest(2)';
         Svest(2) Svest(1)'];