User`s guide

Digital Filter Design
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5Digital Filter Design
Purpose Design and implement a variety of digital FIR and IIR filters.
Library Filtering / Filter Designs
Description The Digital Filter Design block implements a digital FIR or IIR filter that you
design using the Filter Design and Analysis Tool graphical user interface,
referred to as FDATool. The block applies the filter to a discrete-time input
signal and outputs the resulting signal.
To learn how to use FDATool, see the FDATool section of the Signal Processing
Toolbox documentation.
Input and Output Characteristics
The block filters each input channel independently over time, preserving the
input size, frame status, and dimension (1-D or 2-D). Depending on input
characteristics, the block considers the input’s channels as the input columns
or individual input elements:
•Sample-based input matrix — Each matrix element is a channel
•Frame-based input matrix — Each matrix column is a channel
•Unoriented 1-D input vector — Each vector element is a channel
Designing the Filter
Double-click the Digital Filter Design block to open FDATool. Use FDATool to
design or directly specify the filter coefficients of a digital FIR or IIR filter. See
the FDATool section of the Signal Processing Toolbox documentation to learn
how to use FDATool.
Tuning the Filter During Simulation
You can tune the filter specifications in FDATool during simulations as long as
your changes do not modify the filter length or filter order. The block’s filter
updates as soon as you apply any filter changes in FDATool.