what filter can be used to remove background noise in my signal?

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I was given a signal with lots of noise, particulary noise from x*100hz where x = (1:1:100).
Below is the frequency representation of this signal (FFT plot):
I am trying to remove all the noise at x*100hz, where x = (1:1:100), but I am not sure what filter should I use.
I first tried a comb filter using filter Design app: below is the magnitude response:
But this does not work on my signal.
The multipand-pass filter may also work, but I am not sure how to define its parameter.
If you happen to know how to remove this type of noise, please share with me.
Big thanks!
  2 Comments
Fan Yang
Fan Yang on 27 Jan 2022
My appologies! "Doesn't work" is a wrong choice of phrase. what happened when I applied this filtered is simply it did not a job that's good enough.
The picture below showed two FFT results, where blue is from the original data, and red is from the comb filtered data (the filter parameter here is identical to the filter describe in my question). The noise is indeed reduced, but lots of them still remains. Even though, for the black line, I tried to crank up the Apass parameter (to 12) and increase the Q factor (to 65) to balance out the unwanted oscillation caused by this filter, the problem remains.
I am wondering if there is a better filter that can outperform the comb filters I designed above to clean this dataset.

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