System identification in Matlab

First data needs to be stored in an iddata object:

HSFiddata = iddata(output_filtered, input, samplingTime);

Then the sate space model is estimated using:

sys = ssest(HSFiddata, 2, 'Ts', samplingTime, 'DisturbanceModel', 'none', 'Form', 'canonical');

sys.a and sys.b now contain matrices A and B of the state space model.