Analysis of Flow Injection Peaks with Orthogonal Polynomials

Abstract

Digitized transient signals such as those acquired in flow injection analysis may be decomposed by a generalized Fourier expansion into a weighted linear combination of discrete orthogonal polynomials. Together, the coefficients from such an expansion form a spectrum analogous to that of the magnitude spectrum of a discrete Fourier transform and provide a useful alternative means of signal identification. This flexible method of representing peak shag in flow injection (and elsewhere) is not reliant upon any single mathematical model. Two families of functions, the Gram and Laguerre polynomials, were investigated. Both series were found to be sensitive to changes in peak shape and able to represent important features of flow injection time domains signals