User`s guide

impulse
11-94
11impulse
Purpose Compute the impulse response of LTI models
Syntax impulse(sys)
impulse(sys,t)
impulse(sys1,sys2,...,sysN)
impulse(sys1,sys2,...,sysN,t)
impulse(sys1,'PlotStyle1',...,sysN,'PlotStyleN')
[y,t,x] = impulse(sys)
Description impulse calcula tes the unit impulse response of a linear system. The i mpulse
response is the response to a Dirac input for continuous-time systems and
to a unit pulse at for discrete-time systems. Zero initial state is assumed
in the state-space case. W hen invoked without left-hand arguments, this
function plots the impulse response on the screen.
impulse(sys) plots the impulse response o f an arbitrary LTI model sys.This
modelcan becontinuous ordiscrete,and SISO or MIMO.The impulse response
of multi-input systems is the collection of impulse responses for each input
channel. The duration of simulation is determined automatically to display the
transient behavior of the response.
impulse(sys,t) sets the simulation horizon explicitly. You can specify either
a final time
t = Tfinal (in seconds), or a vector of evenly spaced time samples
of the form
t = 0:dt:Tfinal
For discrete system s, the spacin g dt should match the sample period. For
continuous systems,
dt beco mes the samp le t ime of the discret ized simulation
model (see “Algorithm”), so make sure to choose
dt small enough to capture
transient phenomena.
To plot the impulse responses of s everal LTI models
sys1,..., sysN on a si n gle
figure, use
impulse(sys1,sys2,...,sysN)
impulse(sys1,sys2,...,sysN,t)
δ
t
()
t 0
=