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Subject: Effect of sampling frequency for FFT
Date: Fri, 30 Oct 2009 15:01:04 +0000 (UTC)
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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?

Thanks already for answers,

-Juho