How to find frequencies of noise to filter

I want to remove noisy frequencies from a data signal. But, I'm not sure the frequencies of the noise.

I tried fft, but the signal is very single sided, so can't read the specific frequencies from the graph we obtain from the following.

x = Data(:,2)

y = fft(x);

n = length(x); % number of samples

f = (0:n-1)*(fs/n); % frequency range

power = abs(y).^2/n; % power of the DFT

How do we find the specific frequencies of noise from a signal?

Answer 1

[Sai Sri Pathuri]

You may not require the frequency of noise to remove it from the signal. If you know the frequency of the signal, you may use the one of the following filters in documentation to remove the noise.

https://www.mathworks.com/help/signal/filter-design.html