各种滤波器的设计

最新推荐文章于 2025-04-21 11:16:40 发布

转载最新推荐文章于 2025-04-21 11:16:40 发布 · 1.3k 阅读

文章标签：

#plot #filter

matlab 专栏收录该内容

21 篇文章

订阅专栏

本文详细介绍了如何使用MATLAB实现不同类型的滤波器，包括低通、高通、带通与带阻滤波器。通过设置采样率、滤波器阶数和截止频率，展示了滤波器频率响应的绘制过程。

fs=8000;		% Sampling rate
filterOrder=5;		% Order of filter

% ====== low-pass filter
cutOffFreq=1000;
[b, a]=butter(filterOrder, cutOffFreq/(fs/2), 'low');
[h, w]=freqz(b, a);
subplot(2,2,1);
plot(w/pi*fs/2, abs(h), '.-');
xlabel('Freq (Hz)'); title('Freq. response of a low-pass filter'); grid on

% ====== high-pass filter
cutOffFreq=2000;
[b, a]=butter(filterOrder, cutOffFreq/(fs/2), 'high');
[h, w]=freqz(b, a);
subplot(2,2,2);
plot(w/pi*fs/2, abs(h), '.-');
xlabel('Freq (Hz)'); title('Freq. response of a high-pass filter'); grid on

% ====== band-pass filter
passBand=[1000, 2000];
[b, a]=butter(filterOrder, passBand/(fs/2));
[h, w]=freqz(b, a);
subplot(2,2,3);
plot(w/pi*fs/2, abs(h), '.-');
xlabel('Freq (Hz)'); title('Freq. response of a band-pass filter'); grid on

% ====== band-stop filter
stopBand=[1000, 2000];
[b, a]=butter(filterOrder, stopBand/(fs/2), 'stop');
[h, w]=freqz(b, a);
subplot(2,2,4);
plot(w/pi*fs/2, abs(h), '.-');
xlabel('Freq (Hz)'); title('Freq. response of a band-stop filter'); grid on