m5.m

硕士CDMA作业

a3=[0,0,1,0,1];%初值
b3=zeros(1,31);
u3=zeros(1,31);
b3(1,1)=a3(1);

for i=2:31
    c31=a3(1);
    c32=a3(2);
    c33=a3(4);
    c34=a3(5);
    for j=2:5
        
        a3(j-1)=a3(j);
    end
   
   d3=c31+c32+c33+c34;
    f3=mod(d3,2);
    if (f3>1)
       a3(5)=0;
    else 
        a3(5)=f3;
    end
   b3(1,i)=a3(1);
end
ms=b3(1,:);%产生m序列
for i=1:31
    u3(1,i)=(-1)^b3(1,i);%映射成u序列
end



aa1=zeros(1,3100);
for i=0:30
    k=100*i+1;
    for  j=k:k+99
        aa1(1,j)=u3(1,i+1);
    end
end
for l=-200:200
     xg=0;
     if (l<0)
         for i=1:3100
             q=l+i+3100;
             while(q>3100)
                 q=q-3100;
             end
               xg=xg+aa1(1,i)*aa1(1,q);
         end
         xg=xg/3100;
    plot(l,xg);   
    hold on
            
        else
            for i=1:3100
                q=l+i;
                while(q>3100)
                     q=q-3100;
                 end
                 
               xg=xg+aa1(1,i)*aa1(1,q);
           end
            xg=xg/3100;
        plot(l,xg);   
        hold on
       end
end
xlabel('延迟时间（×100）');
ylabel('m序列自相关函数');