ftf1.m

利用ＦＴＦ算法实现了信道均衡的原程序代码。

function [e1,e2,y]=ftf1(x,d,n,N)   
t=0.99;Eb0=0.5;Ef0=Eb0;Q=zeros(N+1,n);r=zeros(n,2);Wf=zeros(N,n);Wb=Wf;W=Wf;
x1=zeros(1,N+1);L=30;
for i=1:n
    for j=1:N+1
        x1(j)=x(j);
    end
    if i==1
        ef1(i)=x1(i);
        ef(i)=ef1(i);
        Ef(i)=t*Ef0+ef1(i)*ef(i);
        Wf(:,i)=0;
        Q(:,i)=[(1/(t*Ef0))*ef1(i);zeros(N,1)];
        r(i,2)=(t*Ef0)/Ef(i);
        eb1(i)=t*Eb0*Q(N+1,i);
        r(i,1)=1/(1/r(i,2)-Q(N+1,i)*eb1(i));
        eb(i)=eb1(i)*r(i,1);
        Eb(i)=t*Eb0+eb(i)*eb1(i);
        Wb(:,i)=Q(1:N,i).*eb(i);
        e1(i)=d(i);
        e(i)=e1(i)*r(i,1);
        W(:,i)=Q(1:N,i)*e(i);
        y(i)=0;
    else
        ef1(i)=x1(1:N+1)*[1;-Wf(:,i-1)];
        ef(i)=ef1(i)*r(i-1,1);
        Ef(i)=t*Ef(i-1)+ef1(i)*ef(i);
        Wf(:,i)=Wf(:,i-1)+Q(1:N,i-1).*ef(i);
        Q(:,i)=[0;Q(1:N,i-1)]+(1/t*Ef(i-1))*[1;-Wf(:,i-1)].*ef1(i);
        r(i,2)=(t*Ef(i-1)/Ef(i))*r(i-1,1);
        eb1(i)=t*Eb(i-1)*Q(N+1,i);
        r(i,1)=1/(1/r(i,2)-Q(N+1,i)*eb1(i));
        eb(i)=eb1(i)*r(i,1);
        Eb(i)=t*Eb(i-1)+eb(i)*eb1(i);
        Q(1:N,i)=Q(1:N,i)+Q(N+1,i).*Wb(:,i-1);
        Wb(:,i)=Wb(:,i-1)+Q(1:N,i).*eb(i);
        e1(i)=0.1*(d(i)-(W(:,i-1))'*(x1(1:N))');
        e(i)=e1(i)*r(i,1);
        e2(i)=e(i)^2;
        W(:,i)=W(:,i-1)+Q(1:N,i)*e(i);
        y(i)=(W(:,i-1))'*(x1(1:N))';
    end
end