Note 49. Designing IIR Filters: Background and Options

The block diagram in Figure 49.1 represents the direct form implementation for an infinite impulse response (IIR) digital filter. The filter consists of an all-zero section followed by an all-pole section. At time n, the all-zero section computes a weighted sum of the inputs from times nM through n. To this result, the all-pole section adds a weighted sum of the previous outputs from times nN through n – 1. The usual mathematical characterizations for an IIR filter are summarized in Math Boxes 49.1 and 49.2.

Figure 49.1. Block diagram for IIR filter

image

The difference equation for the ...

Get Notes on Digital Signal Processing: Practical Recipes for Design, Analysis and Implementation now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.