I have a signal that I sample at some frequency (currently 100Hz), and want to extract low frequency information (between 0.8 and 3 Hz)
I have three constraints on this:
- I would prefer to compute FFTs on small data segments, ideally no longer than 5 seconds.
- I require high resolution on this information - 0.033 Hz between bins or better. I need to accurate resolve the frequencies at this resolution.
- I do not need to resolve the difference between closely spaced frequencies - just one frequency, accurately.
How do i go about doing this? This page suggests that increasing sample frequency makes things worse, and that i need more points - which i would prefer to avoid. Additionally, This page suggests that 0-padding will not add any actual resolution. How accurate is this?