Lowpass filter with L=50?

Question

Dick Rusell 2014-10-9

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/157949-lowpass-filter-with-l-50

评论： Star Strider 2014-10-9

I'm not sure how to make a lowpass filter with L=50, cutoff frequency 1100Hz with omegac, and a sampling frequency of 8000Hz using the Fourier Series Method.

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Star Strider 2014-10-9

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/157949-lowpass-filter-with-l-50#answer_154489

在 MATLAB Online 中打开

I would use the fir1 function. It seems to do what you want.

Here is my approach:

Fs = 8.0E+3;
Fn = Fs/2;
Fc = 1.1E3;
Fcn = Fc/Fn;
L = 50;
b = fir1(L, Fcn);
figure(1)
freqz(b, 1, 128)

Does it do what you want?

2 个评论
显示无隐藏无

Dick Rusell 2014-10-9

I forgot to specify that we had the use the Fourier Series Method by finding h.

Star Strider 2014-10-9

That definitely changes things.

The best resource I can find on that is Low-Pass Filtering by FFT Convolution that also has MATLAB code. All you would need to do is to modify it to your Fs and L. (It’s not an image, so you can copy-paste the code directly from the page.)

I can’t find any MATLAB functions that implement it directly.

请先登录，再进行评论。