apply notch filter on periodic noise in matlab

main.m
load('noisy_signal.mat'); % replace with your signal filename
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main.m
Pxx = abs(fft(noisy_signal)).^2;
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main.m
Fs = 1000; % replace with your sampling frequency
f = linspace(0, Fs/2, numel(Pxx)/2+1);
plot(f, Pxx(1:numel(Pxx)/2+1));
xlabel('Frequency (Hz)');
ylabel('Power');
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main.m
notch_freq = 60; % replace with your noise frequency
Q = 30; % quality factor
wo = notch_freq/(Fs/2);
bw = wo/Q;
[b,a] = iirnotch(wo,bw);
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main.m
filtered_signal = filtfilt(b,a,noisy_signal);
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main.m
plot(t, noisy_signal);
hold on;
plot(t, filtered_signal);
xlabel('Time (s)');
ylabel('Amplitude');
legend('Original', 'Filtered');
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