4PSK_蒙特卡洛仿真_matlab

%function[pb,ps]=cm_sm32(snr_in_dB) clear all snr_in_dB=1 N=10000; E=1; snr=10^(snr_in_dB/10); sgma=sqrt(E/snr)/2; s00=[1 0]; s01=[0 1]; s11=[-1 0]; s10=[0 -1]; for i=1:N, temp=rand; if(temp<0.25), dsource1(i)=0; dsource2(i)=0; elseif(temp<0.5), dsource1(i)=0; dsource2(i)=1; elseif(temp<0.75), dsource1(i)=1; dsource2(i)=0; else dsource1(i)=1; dsource2(i)=1; end; end; numofsymbolerror=0; numofbiterror=0; for i=1:N, n(1)=gngauss(sgma); n(2)=gngauss(sgma); if((dsource1(i)==0) & (dsource2(i)==0)), r=s00+n; elseif((dsource1(i)==0) & (dsource2(i)==1)), r=s01+n; elseif((dsource1(i)==1) & (dsource2(i)==0)), r=s10+n; else r=s11+n; end; c00=dot(r , s00); c01=dot(r , s01); c10=dot(r , s10); c11=dot(r , s11); c_max=max([c00 c01 c10 c11]); if(c00==c_max) decis1=0;decis2=0; elseif(c01==c_max) decis1=0;decis2=1; elseif(c10==c_max) decis1=1;decis2=0; else decis1=1;decis2=1; end; symbolerror=0; if(decis1~=dsource1(i)), numofbiterror=numofbiterror+1; symbolerror=1; end; if(decis2~=dsource2(i)), numofbiterror=numofbiterror+1; symbolerror=1; end; if(symbolerror==1), numofsymbolerror=numofsymbolerror+1; end; end; ps=numofsymbolerror/N; pb=numofbiterror/(2*N);