alamouti_code_sim_2tx1rx_pe.m

在建立独立信道模型的基础上

% the pro. is to simulate alamouti code scheme for BPSK BER in the case of 2Tx-1Rx.
function y=Alamouti_code_sim_2Tx1Rx_Pe(snrindB,sgma)
N=500000;
snr=10^(snrindB/10);
E=snr;
E1=sgma*sqrt(E);
s0=E1;
s1=-E1;
for i1=1:N/10000
   for i=1:10000
   temp=rand;
   if(temp<0.5)
      dsource1(i)=0;
   else
     dsource1(i)=1;
  end;
end;
numofbiterror(i1)=0;
for i=1:10000
   a0=rayleigh(sgma);
   a1=rayleigh(sgma);
   n0=gngauss(sgma);
   n1=gngauss(sgma);
   Q0=2*pi*rand;
   Q1=2*pi*rand;
   if (dsource1(i)==0)
      dists0_s0=((a0^2+a1^2-1)*s0+a0*n0*cos(Q0)+a1*n1*cos(Q1))^2;
      dists0_s1=((a0^2+a1^2)*s0-s1+a0*n0*cos(Q0)+a1*n1*cos(Q1))^2;
      if (dists0_s0<dists0_s1)
         decis1=0;
      else
         decis1=1;
      end;
   else
      dists1_s0=((a0^2+a1^2)*s1-s0-a0*n1*cos(Q0)+a1*n0*cos(Q1))^2;
      dists1_s1=((a0^2+a1^2-1)*s1-a0*n1*cos(Q0)+a1*n0*cos(Q1))^2;
      if (dists1_s0<dists1_s1)
         decis1=0;
      else
         decis1=1;
      end;
   end;
   if(decis1~=dsource1(i))
      numofbiterror(i1)=numofbiterror(i1)+1; 
   end;
end;
numofbiterror(i1)
end;
total_numofbiterror=sum(numofbiterror);
y=total_numofbiterror/N;