A Pragmatic* Introduction to Signal Processing

 with applications in scientific measurement

An illustrated essay with free software and spreadsheet templates to download

Last updated  March, 2024.

A retirement project created and maintained by
Tom O'Haver , Professor Emeritus, Department of Chemistry and Biochemistry

Have a question or suggestion? E-mail me: toh@umd.edu. Join our group on Facebook

No cost, no
ads, no sign-in/registration, no eye candy, no cookies, no hype, no Java, no Flash, no kidding. Completely free since 1993.

This essay is also available as a 537-page printable document written in Microsoft Word and saved in
Word *     and  PDF formats.
Readability index

* Word 365 displays working GIF animations.

The paperback version, ISBN 9798378715381 by Kindle Direct Publishing, is available from Amazon.

This entire web site can be downloaded in archived HTML format complete with all linked software (~600 MBytes). 

  Check out the amazing feedback from users 

Introduction   Fourier deconvolution 
Signal arithmetic  Fourier filter 
Signals and noise  Wavelets and wavelet denoising
Smoothing  Integration and peak
area measurement 
Differentiation  Curve fitting A:
Linear Least Squares
Peak sharpening   Curve fitting B:
Multicomponent Spectroscopy 
Harmonic analysis 
Curve fitting C: Non-linear
Iterative Curve Fitting
Fourier convolution  A Combination of Methods

* Pragmatic: Relating to matters of fact or practical affairs, often to the exclusion of intellectual or artistic matters; practical as opposed to idealistic.

Appendix and Case Studies

The Animated Zoo of Tools and Demos 

 Catalog of downloadable software and templates

Interactive Signal Processing Tools for Matlab

Spreadsheets for Measurement Calibration

Peak Finding and
Measurement 
 Interactive Fourier Filter
Interactive Smoothing, Derivative,
and Signal Analysis  
  Peak Fitter 
(Matlab File Exchange
Pick of the Week)
 Interactive Power Spectrum Demo 
  Interactive Peak Fitter   

Python: a free and fast alternative

Artificial Intelligence and Signal Processing

Live Scripts for smoothing, differentiationdeconvolution, peak detection, and iterative peak fitting

Areas of application where these programs are being applied  (PDF file)

Citations in published papers  (PDF file)  updated

Afterword

From Telegraph Cables to Artificial Intelligence: Unlocking the Power of Data (PDF file)

Making Waves: The basic math of sound and music. (PowerPoint)


Software used in this essay


Matlab, a high-performance commercial numerical computing environment and programming language that is widely used in research and education. For Windows, Macintosh, and Linux.  Lower-cost Home and Student versions available.



  

Octave, a freely downloadable alternative to Matlab, mostly compatible. For Windows, Macintosh, and Linux.


 

Python, with the Spyder desktop interface, a fast and free general purpose language for Windows, Unix, and Macintosh.


Click to enlarge    Click to
          enlarge

Microsoft Excel                    OpenOffice Calc


Acknowledgements
Thanks to my graduate students, many of whom worked with the techniques described within, to M. Farooq Wahab for his many contributions and for many fruitful discussions, to Baldassarre Cesarano for his close reading and typographical correction of this text, to Dr. Raphael Attie of NASA/Goddard Space Flight Center for corrections, to Diederick C. Niehorster of The University of Hong Kong for code contributions, to Yuri Kalambet of Ampersand Ltd. for mathematical insights, and to the many email correspondents who have made suggestions, asked questions, caught errors, and have shown me new types of data and new applications that have broadened the scope of this work.


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Copyright (c) 2023 Thomas C. O'Haver (toh@umd.edu)
 
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
First edition created in 1995. Last updated April, 2023. Created with SeaMonkey. This site is a retirement project and international community service, created and maintained by Prof. Tom O'Haver, Professor Emeritus, Department of Chemistry and Biochemistry, The University of Maryland at College Park, currently residing in Naples, FL. Comments, suggestions and questions should be directed to Prof. O'Haver at toh@umd.edu, currently residing in Naples, FL, and in Silver Spring, MD.