How to create a frequency domain bandstop filter?

Hi

I have a signal and i want to create a frequency-domain bandstop filter to remove a noise of 1100 Hz. i have already removed this frequency by using IIR notch filter. Now i want to learn how can i create a frequency domain bandstop filter?

Can someone please guide?

Thank you in advance

Answer 1

[Star Strider]

Use the fftfilt function, and the FIR filter that produces the desired result.

A suitable, simple notch filter —

Fs = 5000;                                              % Sampling Frequency (Must Be > 2200)
Fn = Fs/2;                                              % Nyquist Frequency
Ws = [1090 1110]/Fn;                                    % Stopband (Normalised)
order = 2^8                                             % Can Be Anything (I Like Powers-Of-2), Higher Values -> Narrower Stopband

order = 256

h1 = fir1(order, Ws, 'stop');                           % Create Filter

figure
freqz(h1, 1, 2^12, Fs)
sgtitle(sprintf('Bode Plot: Order %d, 1100 Hz Stopband Filter', order))

Use the correct Sampling Frequency. Experiment to get different filter designs.

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[Shehzaib Shafique]

Thank you so much sir. It really helped a lot

[Star Strider]

As always, my pleasure!

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