snr=10;
N=input('number');   %數據長度
Es=3;
g=[1 0 1;0 0 1];  %卷積碼編碼器兩路的沖激響應
x=round(rand(1,N)); %產生信源
for i=1:N/2; %串并變換
   x1(i)=x(2*i-1);
x2(i)=x(2*i);
end; 
z=cnvc(g,x1,x2);  %進行(3,2,3)卷積碼編碼，z為三行的向量
len=size(z,2);
zt=z.';
for i=1:len   %進行8PSK映射，得到信號點在星座圖上的位置
   f(i)=bin2deci(zt(i,:)); 
   if ((f(i)>=3)&(f(i)<7))   %在星座圖上處于0.75pi,pi,1.25pi和1.5pi的點
      R(i)=awgn(sqrt(Es)*cos(2*pi*f(i)/8),snr,'measured'); 
      H(i)=awgn(sqrt(Es)*sin(2*pi*f(i)/8),snr,'measured'); 
      T(i)=pi+atan(H(i)/R(i)); 
   elseif f(i)<3  %在星座圖上處于0,0.25pi,0.5pi的點
      R(i)=awgn(sqrt(Es)*cos(2*pi*f(i)/8),snr,'measured'); 
      H(i)=awgn(sqrt(Es)*sin(2*pi*f(i)/8),snr,'measured'); 
      T(i)=atan(H(i)/R(i)); 
   else   %在星座圖上處于1.75pi的點
      R(i)=awgn(sqrt(Es)*cos(2*pi*f(i)/8),snr,'measured'); 
      H(i)=awgn(sqrt(Es)*sin(2*pi*f(i)/8),snr,'measured'); 
      T(i)=2*pi+atan(H(i)/R(i)); 
   end; 
end;