How Do I Fix It?frestimate does not support estimating frequency response estimation of Simulink
models with blocks that model noise. Locate such blocks with frest.findSources and
disable them using the BlocksToHoldConstant option of frestimate.If you need to estimate a model with noise, use frestimate to simulate an output signal
from your Simulink model for estimation—without modifying your model. Then, use the
Signal Processing Toolbox™ or System Identification Toolbox software to estimate a
model.To simulate the output of your model in response to a specified input signal:(^1) Create a random input signal. For example:
in = frest.Random('Ts',0.001,'NumSamples',1e4);
You can also specify your own custom signal as a timeseries object. For example:
t = 0:0.001:10;
y = sin(2pit);
in_ts = timeseries(y,t);
5 Frequency Response Estimation