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From: "Darren " <dgoshi@ucla.edu>
Newsgroups: comp.soft-sys.matlab
Subject: Re: fft amplitude relationship
Date: Mon, 5 Jan 2009 23:48:01 +0000 (UTC)
Organization: University of California Los Angeles
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Can someone point me to a technical reference/document that explains or discusses this fft (time/freq) amplitude scaling concept. Thanks,

Darren


"Ken Garrard" <ken_garrardAT@ncsuDOT.edu> wrote in message <g1jvv5$pq4$1@fred.mathworks.com>...
> "Bruce " <italianasa84@gmail.com> wrote in message 
> <g1juri$c4v$1@fred.mathworks.com>...
> > Thanks, what you mentioned was what I was looking for.
> > - Bruce
> 
> Bruce,
> 
> Walter's answer is incomplete.  The DC and Nyquist values 
> are unique and therefore do not have a 2 in the scale 
> factor.
> 
> time(DC)      = frequency(DC) / N
> time(Nyquist) = frequency(Nyquist) / N
> time(all other points) = frequency(all other points) * 2 / N
> 
> Note that there is no Nyquist value for odd N.
> 
> Ken
>