Specifications

Time Delays
2-43
Time Delays
Using the ioDelay, InputDelay,andOutputDelay properties of LTI objects,
you can specify delays in both continuous- and discrete-time LTI models. With
these properties, you can, for example, represent:
•LTI models with independent delays for each input/output pair. For
example, the continuous-time model with transfer function
•State-space models with delayed inputs and/or delayed outputs. For
example,
where is the time delay between the input and the state vector ,
and is the time delay between and the output .
You can assign the delay properties
ioDelay, InputDelay,andOutputDelay
either when first creating your model with the tf, zpk, ss,orfrd constructors,
or later with the
set command (see “LTI Properties and Methods” on page 2-4
for details).
Supported Functionality
Most analysis commands support time delays, including:
•All time and frequency response commands
•Conversions between model types
•Continuous-to-discrete conversions (
c2d)
•Horizontal and vertical concatenation
•Series, parallel, and feedback interconnections of discrete-time models with
delays
Hs
()
e
0.1s–
2
s
---
e
0.3s–
s 1+
s 10+
---------------
10 e
0.2s–
s 1–
s 5+
------------
=
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