limwiener.m

自适应滤波器程序

%wiener滤波器，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。175－176页
clc;clear all;close all;
f1=50;ts=1/1000;n=1:256;N=256;M=20;
x=2*sin(2*pi*f1*n*ts)+1.4*sin(2*pi*f1*7*n*ts);
x1=1.4*sin(2*pi*f1*7*n*ts);
figure
plot(x1)
d=1.4*sin(2*pi*f1*7*n*ts);
for m=0:M-1
    s=0;
    for n=0:N-1-m
        s=s+x(n+1)*x(n+m+1)/N;
    end
    r(m+1)=s;
end
R=toeplitz(r);
for m=0:M-1
    s=0;
    for n=0:N-1-m
        s=s+x(n+1)*d(n+m+1)/N;
    end
    r(m+1)=s;
end
w=inv(R)*r';
length(w)
for n=0:N-1
    if n<=M-1
        s=0;
    for i=0:n
        s=s+w(i+1)*x(n-i+1);
    end
    y(n+1)=s;
    else
        s=0;
        for i=0:M-1
            s=s+w(i+1)*x(n-i+1);
        end
        y(n+1)=s;
    end
end
figure
plot(y)