FFT result evaluation

From: Alexander Rentschler (arentschler_at_ew.tu-darmstadt.de)
Date: 11/10/04 

Date: Wed, 10 Nov 2004 10:28:20 +0100

I have a signal with harmonics that are not integer multiples of the
fundamental frequency. So it is not possible to guarantee that the FFT -
Window get a full period of each harmonic of the analysed signal. The result
of the FFT is a distributed spectrum for each harmonic and it is not
possible to find out the correct magnitude of the harmonics. Is it possible
to calculate the correct signal magnitude from the distributed spectrum for
each harmonic ? I found a way to calculate the magnitude for each
distributed spectrum, but I don't find the correct mathematical description
for this problem. Has anybody an idea how to define this mathematically.

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