An Introduction to Signal Processing in Chemical Analysis

An illustrated essay with software available for free download

Last updated May, 2009

Tom O'Haver
Professor Emeritus
Department of Chemistry and Biochemistry
University of Maryland at College Park
E-mail: toh@umd.edu

This essay is also available as a single 38-page printable document in OpenOffice, Word , and PDF formats.

IntroductionConvolution
Signal arithmeticDeconvolution
Signals and noiseFourier filter
SmoothingIntegration and peak area measurment
DifferentiationCurve fitting A: Linear Least Squares
Resolution enhancementCurve fitting B: Multicomponent Spectroscopy
Harmonic analysisCurve fitting C: Non-linear Iterative Curve Fitting  updated.gif

Software used to generate the figures and examples:

Programs written for Matlab (PC, Macintosh, or Unix):

Peak Finding and Measurement updated.gif Interactive Power Spectrum Demo
Interactive Smoothing Interactive Fourier Filter
Interactive Derivative Interactive Peak Fitter updated.gif
Interactive Resolution Enhancement The TFit Method for quantitative absorption spectroscopy

Unsolicited Comments from Users:

"I find your Introduction an excellent starting point."

" ... very useful for teaching in an Instrumentation course for M.Sc postgraduates in analytical chemistry. The sequence of the topics and the explanations are very clear."

"[Y]our web site has such excellent content...."

"I tried the demo version of SPECTRUM and I think is a very useful tool for the introduction of signal processing to analytical chemistry students."

" ... a splendid program."

"I have been reviewing your webpage on signal processing and am very impressed with the clarity of the presentation."

"...really clear and concise."

"Thanks...for your excellent code."

"Congratulations on a very useful and rather easy tool."

First edition created in 1995. Last updated May 16, 2009. This page is maintained by Prof. Tom O'Haver, Department of Chemistry and Biochemistry, The University of Maryland at College Park. Comments, suggestions and questions should be directed to Prof. O'Haver at toh@umd.edu. Number of unique visits to this site since May 17, 2008: