limlsl.m

自适应滤波器程序

%LSL算法，选用电力系统谐波信号作为输入信号。参考书目：现代信号处理(第二版），张贤达，清华大学出版社。237页
clear all;close all;
f1=50;ts=1/1000;n=1:256;N=256;
d=2*sin(2*pi*f1*n*ts)+1.4*sin(2*pi*f1*7*n*ts);
y1=2*sin(2*pi*f1*n*ts);
x=sin(2*pi*f1*n*ts+pi/2);M=3;lamda=0.99;
eb(:,1)=zeros(1,M);
delta(:,1)=zeros(1,M);
gama(:,1)=ones(1,M);
Ef(:,1)=ones(1,M);
Eb(:,1)=ones(1,M);
for n=1:N
    eb(1,n)=x(n);
    ef(1,n)=x(n);
end
for n=2:N
    Eb(1,n)=Ef(1,n-1)+x(n-1)^2;
    Ef(1,n)=Ef(1,n-1)+x(n-1)^2;
    gama(1,n)=1;
end
for m=1:M-1
    for n=2:N
        delta(m+1,n)=delta(m+1,n-1)+eb(m,n-1)*ef(m,n)/gama(m,n-1);
        ef(m+1,n)=ef(m,n)-delta(m+1,n)*eb(m,n-1)/Eb(m,n-1);
        eb(m+1,n)=eb(m,n-1)-delta(m+1,n)*ef(m,n)/Eb(m,n);
        Ef(m+1,n)=Ef(m,n)-delta(m+1,n)^2/Eb(m,n-1);
        Eb(m+1,n)=Eb(m,n-1)-delta(m+1,n)^2/Ef(m,n);
        gama(m+1,n-1)=gama(m,n-1)-eb(m,n-1)^2/Eb(m,n-1);
        Kf(m,n)=delta(m+1,n)/Ef(m,n);
        Kb(m,n)=delta(m+1,n)/Eb(m,n-1);
    end
end
    for n=1:N
        a(1,n)=Kb(1,n)-Kf(1,n)*Kb(2,n);
        a(2,n)=Kb(2,n);

    for m=1:M
        if n<=M-1
            b(m)=0;
        else
        b(m)=x(n-m+1);
        end
    end
    X(:,n)=b';
y(n)=a(:,n)'*X(2:end,n);
    end
plot(y)