Maximum Discrimination Approach for Classification of Nearly Identical Signatures

Spectroscopic analysis is used throughout industry, academia, and other areas to differentiate and identify compounds. In many cases the compounds have highly similar spectral structures, i.e., spectral overlap and may only readily be identified as belonging to a class of materials. Current analytical methods perform well when there are clearly discernible peaks within the spectra but are known to lose discrimination power as the spectra of interest become more and more similar. To overcome this loss in detection power we propose a novel method for determining the maximum discrimination spectral bands, known as the maximum discrimination approach (MDA). MDA is based upon determining the statistical distance between two spectra for each band, and is derived by assuming each spectrum is the result of estimating the power spectral density of Gaussian noise. We demonstrate the ability of MDA to find maximum discrimination spectral bands using the spectral data of gasoline and kerosoene, two related mixtures with similar spectral content.