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Pseudorandom binary sequence input signal

Use a `frest.PRBS`

object to represent a pseudorandom binary
sequence (PRBS) input signal for frequency response estimation. A PRBS signal is a
deterministic signal that shifts between two values and has white-noise-like properties. A
PRBS signal is inherently periodic with a maximum period length of
2^{n}–1, where *n* is the PRBS
order.

PRBS signals reduce total estimation time compared to using sinestream input signals, while producing comparable estimation results. PRBS signals are useful for estimating frequency responses for communications and power electronics systems with high-frequency switching components, such as pulse-width modulation (PWM) generators.

You can use a PRBS input signal for estimation at the command line or in the **Model
Linearizer** app. The estimation algorithm injects the PRBS signal at the input point
you specify for estimation and measures the response at the output point. For more
information, see PRBS Input Signals.

To view a plot of your input signal, type `plot(input)`

. To create a
`timeseries`

object for your input signal, use the `generateTimeseries`

command.

creates a PRBS signal with parameters based on the dynamics of the linear system
`input`

= frest.PRBS(`sys`

)`sys`

. For instance, if you have an exact linearization of your
system, you can use it to initialize the parameters.

creates a PRBS signal with properties
specified using one or more name-value pairs. Enclose each property name in quotes.`input`

= frest.PRBS(`Name,Value`

)

`frestimate` | Frequency response estimation of Simulink models |

`generateTimeseries` | Generate time-domain data for input signal |

`frest.simCompare` | Plot time-domain simulation of nonlinear and linear models |

`frest.simView` | Plot frequency response model in time- and frequency-domain |

`getSimulationTime` | Final time of simulation for frequency response estimation |

In the **Model Linearizer**, to use a PRBS input signal for estimation, on the
**Estimation** tab, select **Input Signal** > **PRBS Pseudorandom Binary Sequence**