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Frequency-Response Models

Frequency-response models obtained using spectral analysis


System IdentificationIdentify models of dynamic systems from measured data


etfeEstimate empirical transfer functions and periodograms
spaEstimate frequency response with fixed frequency resolution using spectral analysis
spafdrEstimate frequency response and spectrum using spectral analysis with frequency-dependent resolution
idfrdFrequency response data or model
getpvecObtain model parameters and associated uncertainty data
setpvecModify values of model parameters
bodeBode plot of frequency response, or magnitude and phase data
bodemag Magnitude-only Bode plot of frequency response
freqrespFrequency response over grid
chgFreqUnitChange frequency units of frequency-response data model

Examples and How To

Estimate Frequency-Response Models in the App

You must have already imported your data into the app and performed any necessary preprocessing operations.

Estimate Frequency-Response Models at the Command Line

You can use the etfe, spa, and spafdr commands to estimate spectral models.


What is a Frequency-Response Model?

A frequency-response model is the frequency response of a linear system evaluated over a range of frequency values.

Data Supported by Frequency-Response Models

Characteristics of data supported for estimation of spectral analysis models.

Selecting the Method for Computing Spectral Models

How to select the method for computing spectral models during estimation in the app and at the command line.

Controlling Frequency Resolution of Spectral Models

Controlling frequency resolution of spectral models during estimation in the app and at the command line.

Spectrum Normalization

The spectrum of a signal is the square of the Fourier transform of the signal.