clc
clear
close all
N=10;  n=500;  
for i=1:n                   
    if rem(i,2)==0   
        x(i)=1; 
        d(i)=x(i);   
    else
        x(i)=-1;
        d(i)=x(i); 
    end           
end
n1=10^(-0.25)*randn(1,n);  
for k=1:n
    x1(k)=x(k)+n1(k);      
end
for v=1:100;
as(v)=x(v);
end 
subplot(2,3,1);plot(as);title('信號');
subplot(2,3,2);plot(n1);title('噪聲');
subplot(2,3,3);plot(x1);title('信號加噪聲');
[e1,e2,y]=ftf1(x1,d,n,N);
for l=1:n
    h(l)=y(l)/x1(l);
end
r=1:500;
subplot(2,3,4);plot(h);title('均衡器沖擊響應');
subplot(2,3,5);semilogy(r,e2);title('學習曲線');xlabel('n疊代次數');ylabel('MSE(均方誤差)');
figure(2)
plot(as);title('信號');
figure()
plot(n1);title('噪聲');
figure()
plot(x1);title('信號加噪聲');
figure()
plot(h);title('均衡器沖擊響應');
figure()
semilogy(r,e2);title('學習曲線');xlabel('n疊代次數');ylabel('MSE(均方誤差)');