08-19-2013 07:48 AM
Hello i have a problem. I am ploting a signal which i got from XY array. Then i need to do FFT on this. Problem is that my sample difference of time(X-axis) is about: 0,00625 which does a 8hz plot on FFT. Is it possible to interpolate this XY array(i mean something simulates new points between X's and Y's) to get more HZ's on FFT plot?
08-19-2013 08:00 AM
Try the express VI called "Align and Resample". You might have to convert your XY data to an evenly sampled waveform first.
08-19-2013 09:15 AM
First, a 0.00625 sampling interval provides a spectrum up to 80 Hz, not 8 Hz.
Second, interpolating or resampling the data will not provide information on higher frequencies. Even if the spectrum shows higher frequency components, they are artifacts. The information is just not present in the data.
You have to sample at higher frequency.
Cheers
Edgar