Problem with standard methods of smoothening in Signals

John Williams answered . 2024-12-21 00:24:40

% Generate noisy signal (example)
fs = 1000; % Sampling frequency
t = 0:1/fs:5; % Time vector
signal = sin(2*pi*10*t) + 0.5*sin(2*pi*50*t) + 2*randn(size(t)); % Noisy signal

% Design high-pass filter to remove low-frequency drift
highpass_cutoff = 0.5; % Cutoff frequency for high-pass filter (adjust as needed)
hp_filter = designfilt('highpassfir', 'FilterOrder', 50, 'CutoffFrequency', highpass_cutoff, 'SampleRate', fs);

% Design low-pass filter to attenuate high-frequency noise
lowpass_cutoff = 30; % Cutoff frequency for low-pass filter (adjust as needed)
lp_filter = designfilt('lowpassfir', 'FilterOrder', 50, 'CutoffFrequency', lowpass_cutoff, 'SampleRate', fs);

% Apply high-pass filter
filtered_signal = filtfilt(hp_filter, signal);

% Apply low-pass filter
filtered_signal = filtfilt(lp_filter, filtered_signal);

% Plot original and filtered signals
figure;
plot(t, signal, 'b', 'LineWidth', 1.5); hold on;
plot(t, filtered_signal, 'r', 'LineWidth', 1.5);
xlabel('Time (s)');
ylabel('Amplitude');
legend('Original Signal', 'Filtered Signal');
title('Cascaded High-pass and Low-pass Filtering');
grid on;

Not satisfied with the answer ?? ASK NOW