psk.txt

实现蒙特卡罗分析

function[pb,ps]=pskmoto(snr_in_dB) 
N=10000; 
E=1;  
snr=10^(snr_in_dB/10);
sgma=sqrt(E/(3*2*snr)); 
n=[0 0];
s000=[1,0]; 
s001=[cos(pi/4),sin(pi/4)]; 
s010=[cos(3*pi/4),sin(3*pi/4)]; 
s011=[0,1]; 
s100=[cos(7*pi/4),sin(7*pi/4)]; 
s101=[0,-1]; 
s110=[-1,0]; 
s111=[cos(5*pi/4),sin(5*pi/4)]; 

 
for i=1:N, 
temp=rand; 
if (temp<0.125),  
dsource1(i)=0; 
dsource2(i)=0; 
dsource3(i)=0; 
elseif (temp<0.25), 
dsource1(i)=0; 
dsource2(i)=0; 
dsource3(i)=1;
elseif (temp<0.375), 
dsource1(i)=0; 
dsource2(i)=1; 
dsource3(i)=0; 
elseif (temp<0.5),
dsource1(i)=0; 
dsource2(i)=1; 
dsource3(i)=1;
elseif (temp<0.625),
dsource1(i)=0; 
dsource2(i)=0; 
dsource3(i)=1;
elseif (temp<0.75),
dsource1(i)=1; 
dsource2(i)=0; 
dsource3(i)=1;
elseif (temp<0.875),
dsource1(i)=0; 
dsource2(i)=1; 
dsource3(i)=1;
else 
dsource1(i)=1; 
dsource2(i)=1; 
dsource3(i)=1;
end
end
numofsymbolerror=0;
numofbiterror=0;
for i=1:N;
    n=gngauss(sgma)
    if((dsource1(i)==0)&(dsource2(i)==0)&(dsource3(i)==0))
        r=s000+n;
    elseif((dsource1(i)==0)&(dsource2(i)==0)&(dsource3(i)==1))
        r=s001+n;
    elseif((dsource1(i)==0)&(dsource2(i)==1)&(dsource3(i)==0))
        r=s010+n;
     elseif((dsource1(i)==0)&(dsource2(i)==1)&(dsource3(i)==1))
        r=s011+n;
     elseif((dsource1(i)==1)&(dsource2(i)==0)&(dsource3(i)==0))
        r=s100+n;
      elseif((dsource1(i)==1)&(dsource2(i)==0)&(dsource3(i)==1))
        r=s101+n;
      elseif((dsource1(i)==1)&(dsource2(i)==1)&(dsource3(i)==0))
        r=s110+n;  
    else
        r=s111+n;
    end
    c000=dot(r,s000);c001=dot(r,s001);c010=dot(r,s010);c011=dot(r,s011);
    c100=dot(r,s100);c101=dot(r,s101);c110=dot(r,s110);c111=dot(r,s111);
c_max=max([c000 c001 c010 c011 c100 c101 c110 c111]); 
if (c000==c_max) 
decis1=0;decis2=0;decis3=0; 
elseif (c001==c_max) 
decis1=0;decis2=0;decis3=1; 
elseif (c010==c_max) 
decis1=0;decis2=1;decis3=0; 
elseif (c011==c_max) 
decis1=0;decis2=1;decis3=1; 
elseif (c100==c_max) 
decis1=1;decis2=0;decis3=0; 
elseif (c101==c_max) 
decis1=1;decis2=0;decis3=1; 
elseif (c110==c_max) 
decis1=1;decis2=1;decis3=0; 
else 
decis1=1;decis2=1;decis3=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 (decis3~=dsource3(i)), 
numofbiterror=numofbiterror+1; 
symbolerror=1; 
end; 
if (symbolerror==1), 
numofsymbolerror=numofsymbolerror+1; 
end; 
end; 
ps=numofsymbolerror/N 
pb=numofbiterror/(3*N)