# Designing a Notch Filter

Started by February 12, 2008
Hi friends,
I need to design a notch filter using matlab..

can anyone tell me if any inbuilt command is available for designing a notch
filter in matlab.how can i specify the frequency which should be attenated
and the bandwidth of notch????

also, i need to design a FIR FILTER using window method. Can i use FDATOOL
for designing it...If so..where should i mention the Number of taps and
window size in FDA designing window???
Thanks and Regards,
you can use MatLab functions like butter(butter worth), cheby1 ,cheby2 (Chebyshev Type I & II), etc
for exp for a bandstop filter like 50Hz notch:

fs = 1000;% sampling frequency
deg = 3;%filter deg
Wn = [45*2/fs,55*2/fs];
[B,A] = butter(deg,Wn,'stop');

filteredSignal = filter(B,A,signal);

maha devi wrote:

Hi friends,
I need to design a notch filter using matlab..

can anyone tell me if any inbuilt command is available for designing a notch filter in matlab.how can i specify the frequency which should be attenated and the bandwidth of notch????

also, i need to design a FIR FILTER using window method. Can i use FDATOOL for designing it...If so..where should i mention the Number of taps and window size in FDA designing window???
Thanks and Regards,

notch filter is as like as bandstop filter but very sharp on cutoff freq, like when you want to damp 50Hz or 60Hz noise from signal.
ya Ali

Abdul Wahab wrote:
Sorry I cant undestand urs Question

I m also student of electrical engineering but i donot read any notch filter till now

Thnks

Abdul wahab

On 2/16/08, emilly wrote: you can use MatLab functions like butter(butter worth), cheby1 ,cheby2 (Chebyshev Type I & II), etc
for exp for a bandstop filter like 50Hz notch:

fs = 1000;% sampling frequency
deg = 3;%filter deg
Wn = [45*2/fs,55*2/fs];
[B,A] = butter(deg,Wn,'stop');

filteredSignal = filter(B,A,signal);

maha devi wrote:
Hi friends,

I need to design a notch filter using matlab..

can anyone tell me if any inbuilt command is available for designing a notch filter in matlab.how can i specify the frequency which should be attenated and the bandwidth of notch????

also, i need to design a FIR FILTER using window method. Can i use FDATOOL for designing it...If so..where should i mention the Number of taps and window size in FDA designing window???