Removing DC component at 0 HZ from acceleration data after fft

8 次查看（过去 30 天）
Adam Levschuk
Adam Levschuk 2020-5-29
评论： Nidhi Singh 2022-2-11
Hello,
After i compute the FFT of my acceleration data (Fs = 50 Hz) i am getting a large spike at 0 Hz (the leftover DC component). I have tried subtarcting the mean and detrending my data (detrend(X,2)).
Here is my code:
n = length(acc(:,1));
accX_fft = fft(acc(:,1),n);
PSD = accX_fft.*conj(accX_fft)/n;
freq = linspace(0,50,length(accX_fft));
L = 1:floor(n/2);
plot(freq(L),PSD(L));
The amplitudes of the frequecieis i want to visualize are already very very small, so the spike at 0 Hz is really distorting the view.
Id appreciate any reccomendation on how to get rid of this spike.
  2 个评论
Ameer Hamza
Ameer Hamza 2020-5-29
If subtracting mean does not work, then it might be some other frequency?
Nidhi Singh
Nidhi Singh 2022-2-11
I am having the same doubt. If subtracting the mean doesn't work, than can we use high pass filter here with fft graph?

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

Ameer Hamza
Ameer Hamza 2020-5-29
As described here: http://blog.originlab.com/how-to-remove-dc-offset-before-performing-fft try using a high-pass filter to remove very low frequencies from your signal. See highpass(): https://www.mathworks.com/help/releases/R2020a/signal/ref/highpass.html

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Fourier Analysis and Filtering 的更多信息

标签

产品


版本

R2020a

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by