Need to find cutoff frequency using frequency spectrum

frequency 100Hz,amplitude 2 phase=0 i generate sine wave,add 100hz noise and get a frequnecy spectrum using FFT in matlab.i want to dicide the type of filter and cutoff frequency to be used to elimate the noise using this frequency spectrum how to do that using matlab?

thank you,

Answer 1

[Star Strider]

I essentially already did all of that in my Answer to I want to remove 50 Hz noise using fir notch filter in ECG

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