Yes, if you are referring to an un-aliased signal, then 5MHz will be the
highest frequency at which the amplitude and phase can be properly computed.
If you consider undersampling, a phenomena where aliasing is
intentionally used, then the answer becomes much more complicated. See
On Thu, Aug 11, 2011 at 3:14 AM, bashir siddiqui
> I have one very simple question. I hope some one will clearify my doubts.
> The range of frequencies covered in the output record from the FFT is 0 to
> 1/2 the sample rate of the acquired data record. For example, a sample rate
> of 20 MS/s (megasamples per second) would give an FFT range of 0 to 10 MHz.
> Does it mean I can only see the proper FFT peak of the signal with maximum
> frequency 5 MHz ?
> I appreciate your help.
UC Santa Cruz Computer Engineering