Understanding convolution is central to understanding filtering, the Discrete Fourier Transform, and other important DSP operations. In this tutorial, R. C. Kim explains convolution using a visual, intuitive, step-by-step method, and relates it to filtering and the DFT.
ScopeFIR can design and analyze Finite Impulse Response (FIR) filters using the Parks-McClellan algorithm and a variety of other methods.
In the classic paper, "An Economical Class of Digital Filters for Decimation and Interpolation", Hogenauer introduced an important class of digital filters called "Cascaded Integrator-Comb", or "CIC" for short (also sometimes called "Hogenauer filters").
Here, Matthew Donadio provides a more gentle introduction to the subject of CIC filters, geared specifically to the needs of practicing DSP designers:
From: R. G. Lyons, UNDERSTANDING DIGITAL SIGNAL PROCESSING, (Appendix F - pages 494-505). © 1997 by Addison Wesley Longman Inc., Reproduced by permission of Addison Wesley Longman. All rights reserved.
The first step in becoming familiar with digital filters is to learn to speak the language used in the filter business.
This page lists digital filter design software tools for DSP. Tools are categorized as Commercial, Open-Source, Freeware, or Web-Based.
Commercial Filter Design Software
Commercial filter design software tools generally have more capabilities than their open/free counterparts, making them more productive to use.
Infinite Impulse Response (IIR) filters are fundamental elements of Digital Signal Processing. This is dspGuru's mini-FAQ of "Frequently Asked Questions" on the subject of IIR filters.
1. IIR Basics
1.1 What are IIR filters? What does "IIR" mean?
IIR filters are one of two primary types of digital filters used in Digital Signal Processing (DSP) applications (the other type being FIR). "IIR" means "Infinite Impulse Response".