How to remove multiple evenly spaced frequency components from digital signal

Hey guy,

the FFT of my acustic signal returned some evenly spaced back group noisey frequencies 3,6,9,12,15hz. To remove them at once, I beliebe I can use a irrnotch or irrcomb. But the example of both functions only demonstrated how to remove a signal frequency component, which is a 60hz notch. I am wondering how can I remove multiple evenly spaced frequency components at once.

[Mathieu NOE]

hello

iircomb will do the job for multiple frequencies - read again the help . yes it will remove the 60 hz tone plus all harmonics

example is given for 11 notches = 60 Hz tone + 10 harmonics will be removed

Design and plot an IIR notch filter with 11 notches (equal to filter order plus 1) that removes a 60 Hz tone (f0) from a signal at 600 Hz(fs). For this example, set the Q factor for the filter to 35 and use it to specify the filter bandwidth.

fs = 600;

fo = 60;

q = 35;

bw = (fo/(fs/2))/q;

[b,a] = iircomb(fs/fo,bw,'notch'); % Note type flag 'notch'