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Re: Fourier decomposition
On 16 Sep 2005 at 19:20, Fred Herzfeld wrote:
> Hello List:
> I am now about to make public some work on signal decomposition. As part
> of the disclosure I will make the statement:
> It is not possible to accurately recover the coefficients (amplitude and
> phase of the individual harmonics) of a function consisting of harmonic
> sinusoidal components, when the Period of the not necessarily present
> fundamental is not known, by using the normal computational procedure of
> either the Fourier Series or the Short term Fourier Transform.
> I would appreciate any and all comments.
Interesting question. Pre-multiplication by ordinary windowing
functions seems to do a pretty good job when recovering the
magnitudes, but I've never looked into what this does to the
phase. I gather from your statement that it screws it up, and
that there is no analogous window function for obtaining phase?
Thanks for your insights...