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arXiv · 1406.2280

Fitting FFT-derived Spectra: Theory, Tool, and Application to Solar Radio Spike Decomposition

Gelu M. Nita·Gregory D. Fleishman·Dale E. Gary·William Marin·Kristine Boone
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Abstract

Spectra derived from fast Fourier transform (FFT) analysis of time-domain data intrinsically contain statistical fluctuations whose distribution depends on the number of accumulated spectra contributing to a measurement. The tail of this distribution, which is essential for separation of the true signal from the statistical fluctuations, deviates noticeably from the normal distribution for a finite number of the accumulations. In this paper we develop a theory to properly account for the statistical fluctuations when fitting a model to a given accumulated spectrum. The method is implemented in software for the purpose of automatically fitting a large body of such FFT-derived spectra. We apply this tool to analyze a portion of a dense cluster of spikes recorded by our FST instrument during a record-breaking event that occurred on 06 Dec 2006. The outcome of this analysis is briefly discussed.

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Gelu M. Nita, Gregory D. Fleishman, Dale E. Gary, William Marin, Kristine Boone. 2014-06-09. Fitting FFT-derived Spectra: Theory, Tool, and Application to Solar Radio Spike Decomposition. https://doi.org/10.1088/0004-637x/789/2/152

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