ssbpskawgn2user.m

这是用Matlab仿真的移动通信中多用户与基站同时通信时的干扰。

N_Trials=1000;
N_number=100;
N_snr=10;
Q=15;
E_M=[ ];
for trials=1:N_Trials
    trials 
noise=randn(1,Q*N_number)+j.*randn(1,Q*N_number); 
 s01=round(rand(1,N_number));
   ss1=s01*2-1;
   pn01=pn_m(15,1)./sqrt(15);
   s1=kron(ss1,pn01);  
 s02=round(rand(1,N_number));
   ss2=s02*2-1;
   pn02=round(rand(1,Q));
   pn2=pn_m(15,1)./sqrt(15);
   s2=kron(ss2,pn02);
sgma=1;
   Error_v=[ ];
 for snr_db=0:1:N_snr
        snr=10.^(snr_db./10);
        N0=2*sgma.^2;
        Eb=snr.*N0;
        yy=sqrt(Eb)*s1+s2+noise;
        Y_M=[ ];
        for k=1:N_number
            ym=yy(1,(k-1)*Q+1:k*Q);
            Y_M=[Y_M;ym];
        end
        ys=Y_M*pn01.';
        y=ys.';
        y_real=real(y);
        s_e=sign(y_real);
        s_e10=(s_e+1)./2;
        Error_snr=sum(abs(s01-s_e10));
        Error_v=[Error_v,Error_snr/N_number];
    end
   E_M=[E_M;Error_v] ;
end
   E_sum=mean(E_M);
   BER=E_sum;
   BER_T=[ ];
   for snr_db=0:1:N_snr
      snr=10.^(snr_db./10);
      BER_THEROY=Qfunct(sqrt(2.*snr));
      BER_T=[BER_T,BER_THEROY];
   end
figure
lpa=1;
i=0:1:N_snr;
semilogy(i,BER,'-r',i,BER_T ,'*g');  
xlabel('E_b/N_0(dB)')
ylabel('BER')
legend('Monte-Carlo', 'Theroetic')