Comb filtering when sampling frequency is not multiplicative of the interference fundamental frequency

Hi all,

I would like to apply a notch comb filter (e.g. by using the iircomb function), but my sampling frequency is 976 Hz and the fundamental frequency of the noise signal is 50 Hz.

Any ideas of how I could achieve that would be greatly appreciated. An alternative would be to use multiple notch filters (e.g. iirnotch) but this would increase dramatically the associated computational costs.

Kind regards, Agamemnon

Answer 1

[Santhana Raj]

Hi,

You have to change the Sampling frequency such that you can get the sampling frequency to be a multiple of noise frequency.

You can do this my a combination of down-sampling and up-sampling. Find a fraction such that the sampling frequency is converted to ANY multiple of noise frequency. Not that it can be any multiple not necessarily 1000Hz.

All the best.