Design and implement digital FIR and IIR filters
Filtering / Filter Implementations
Use this block to design, analyze, and efficiently implement floating-point filters. The following blocks also implement digital filters, but serve slightly different purposes:
Discrete FIR Filter and Biquad Filter— Use to efficiently implement floating-point or fixed-point filters that you have already designed. These blocks provide the same exact filter implementation as the Digital Filter Design block.
Filter Realization Wizard — Use to implement floating-point or fixed-point filters built from Sum, Gain, and Unit Delay blocks. You can either design the filter within this block, or import the coefficients of a filter that you designed elsewhere.
The Digital Filter Design block implements a digital FIR or IIR filter that you design
using the filter designer (
filterDesigner) app. This block provides
the same filter implementation as the Discrete FIR Filter or Biquad Filter
You must specify whether the block performs frame-based or sample-based processing on the input
by setting the Input processing parameter. The block applies the
specified filter to each channel of a discrete-time input signal, and outputs the
result. The outputs of the block numerically match the outputs of the Discrete FIR
Filter or Biquad Filter block, the MATLAB®
filter function, and the DSP System
The sampling frequency, Fs, that you specify in the filter designer app should be identical to the sampling frequency of the input to the Digital Filter Design block. When the sampling frequencies do not match, the Digital Filter Design block returns a warning message and inherits the sampling frequency of the input block.
Double-click the Digital Filter Design block to open filter designer. Use filter designer to design or import a digital FIR or IIR filter. To learn how to design filters with this block and filter designer, see the following topics:
You can tune the filter specifications in filter designer during simulations as long as your changes do not modify the filter length or filter order. The filter updates as soon as you apply any filter changes in filter designer.
For more information about the parameters on this dialog box, see Getting Started with Filter Designer (Signal Processing Toolbox).
Double-precision floating point
Single-precision floating point
|Discrete FIR Filter||DSP System Toolbox|
|Biquad Filter||DSP System Toolbox|
|Analog Filter Design||DSP System Toolbox|
|Window Function||DSP System Toolbox|
|DSP System Toolbox|
|DSP System Toolbox|
|Signal Processing Toolbox|
To learn how to use this block and filter designer, see the following:
Generated code relies on
memset functions (string.h) under certain conditions.