Design low pass filter with a given transfer function
4 views (last 30 days)
Show older comments
I must design a low-pass filter with a given transfer function in z-domain:
H(z) = (1-z^(-6))^2 / (1-z^(-1))^2
Considering the x signal (1x2000) I want to filter, i wrote
N = 2000;
h1 = zeros(1,N);
%
% a. Low-Pass Filter
for i = 1:N
if (i == 1)
h1(1) = 1;
a1(1) = 1;
b1(1) = 1;
else
if (i == 2)
h1(2) = 1/(1-2*x(1));
b1(2) = 1;
a1(2) = 1-2*x(1);
else
if ((i == 3) || (i == 4) || (i == 5) || (i == 6))
h1(i) = 1/(1+x(i-2)-2*(x(i-1)));
b1(i) = 1;
a1(i) = (1+x(i-2)-2*(x(i-1)));
else
if ((i == 7) || (i == 8) || (i == 9) || (i == 10) || (i == 11) || (i == 12))
h1(i) = ((1-2*x(i-6)))/(1+(x(i-2))-2*(x(i-1)));
b1(i) = (1-2*x(i-6));
a1(i) = (1+(x(i-2))-2*(x(i-1)));
else
h1(i) = ((1+(x(i-12))-2*(x(i-6))))/(1+(x(i-2))-2*x(i-1));
b1(i) = ((1+(x(i-12))-2*(x(i-6))));
a1(i) = (1+(x(i-2))-2*x(i-1));
end
end
end
end
end
figure,
freqz(b1,a1,512,fc);
y = filter(b1,a1,x);
Is it correct? I don't think so because the plot it is a mess and definitively not a low-pass! What is it wrong?
0 Comments
Answers (0)
See Also
Categories
Find more on Analog Filters in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!