NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
The Fast Fourier Transform for Experimentalists, Part I: Concepts
Published
Author(s)
D Donnelly, Bert W. Rust
Abstract
The discrete Fourier transform (DFT) is a widely used tool for the analysis of measured time series data. The Cooley-Tukey fast Fourier transform (FFT) algorithm gives an extremely fast and efficient implementation of the DFT. This is the first of a series of three articles which will describe the use of the FFT for experimental practitioners. This installment gives fundamental definitions and tells how to use the FFT to estimate power and amplitude spectra of a measured time series. It discusses the use of zero padding, the problem of aliasing, the relationship of the inverse DFT to Fourier series expansions, and the use of tapering windows to reduce the sidelobes on the peaks in an estimated spectrum.
Donnelly, D.
and Rust, B.
(2005),
The Fast Fourier Transform for Experimentalists, Part I: Concepts, Computing in Science & Engineering, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=150008
(Accessed October 14, 2025)