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From: heath@ll.mit.edu (Greg Heath)
Newsgroups: comp.dsp,comp.soft-sys.matlab
Subject: Re: DFT of an irregular time-spacing signal
Date: 22 Oct 2002 19:34:48 -0700
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heath@ll.mit.edu (Greg Heath) wrote in message news:<9e910d7a.0210211421.4fcf9eb@posting.google.com>...
> "Chia C Chong" <Chia.Chong@ee.ed.ac.uk> wrote in message news:<ap102a$6ce$1@scotsman.ed.ac.uk>...
> > Hi there!
> > 
> > I have a signal, y which has irregular time-spacing. I would like to find
> > the power spectrum of this signal. Since the signal has irregular
> > time-spacing, I guess I can't simply perform the DFT using the fft command
> > in Matlab?? If so, what method should I used in order to find the power
> > spectrum of y?
> 
> help dft
> 
> Greg

I just replied to this 1st reply but cannot reply to my 2nd reply 
directly (;>).

Third reply: As indicated in my previous post, I searched *within 
newsgoups* on google using "fourier nonequispaced". I found the 
following threads containing references:

sci.math.num-analysis

Non-equidistant discrete data: Fourier transform, Bruce Johnson,
May 28,1999.
FFT with non equidistant sample, Peter Spelluci, Apr 11, 2001
FFT algorithm for "sparse" input, Sean Moore, Mar 7, 1995

Hope this helps,

Greg