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From: Greg Heath <heath@alumni.brown.edu>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Effect of sampling frequency for FFT
Date: Sat, 31 Oct 2009 23:36:22 -0700 (PDT)
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On Nov 1, 2:27 am, Greg Heath <he...@alumni.brown.edu> wrote:
> On Oct 30, 11:01 am, "juho salminen" <jssal...@cc.hut.fi> wrote:
>
> > Hi,
>
> > I have done some tests with artificial sinusoidial data with white noise added on it. It seems, that the higher sampling frequency I have, the better is signal to noise ratio in FFT. With this I mean, that I take FFT with constant window length, let's say 500 samples. Signal itself is kept constant, let's say 30Hz.
> > Highter sampling frequency then, of course, reduces the time window size.
> > This should simulate measurements of some sinusoid with  different sampling frequencies
>
> > Do you know what would cause better SNG values, when sampling frequency increases?
>
> SNR is independent of Fs.
-----SNIP

Whoops. You mean SNR of the FFT.
I'll look at that now.
Greg