Hey guys! I'm fairly new with signal processing in matlab. I have some labdata that are corrupted by noise. I would like to make a (butterworth) bandpass filter between approx. 0.5 kHz and 1.5 kHz. I have tried a lot of different approaches from browsing the net. My latest attempt looks like this:
This is the output i get (3rd subplot) when i plot the "filtsig" vs. the frequency (freq). You can see the original spectrum (intended) but the filtered spectrum does not even show up:
and this is the format of my data from the time series and the spectrum (input channel and output channel):
I have spend a lot of hours trying to figure out how to do the bandpass properly. Can some of you figure out what is wrong?