m.m

硕士CDMA作业

%1+x+x^6%
a=zeros(63,7)
b=zeros(7,1)
c=zeros(1,189)
r=zeros(1,201)
b=[0 0 0 0 0 1 0]
a(1,6)=1
for i=1:63,
    b(1,7)=b(1,6);
    b(1,6)=b(1,5);
    b(1,5)=b(1,4);
    b(1,4)=b(1,3);
    b(1,3)=b(1,2);
    b(1,2)=b(1,1);
    b(1,1)=xor(b(1,1),b(1,7));
    for j=1:7,
        a(i,j)=b(1,j);
    end
end
for k=1:63,
    if (a(k,7)==0),
        c(1,k)=1;
    else
        c(1,k)=-1; 
    end
end
for k=1:63,
    c(1,k+63)=c(1,k);
    c(1,k+126)=c(1,k);
end
    
for t=0:100,
   s=0 
   for n=1:63,
        s=s+c(1,n)*c(1,n+t);
    end
    r(1,t+101)=s/63
end
for k=1:100,
    r(1,k)=r(1,202-k)
end
    plot((-100:100),r)
    xlabel('1+x+x^6的自相关函数')