Nonparametric time-variant frequency response function estimates using arbitrary excitations

@article{Pintelon2015NonparametricTF,
  title={Nonparametric time-variant frequency response function estimates using arbitrary excitations},
  author={Rik Pintelon and Ebrahim Louarroudi and John Lataire},
  journal={Automatica},
  year={2015},
  volume={51},
  pages={308-317}
}
The time-variant frequency response function (TV-FRF) uniquely characterizes the dynamic behaviour of a linear timevariant (LTV) system. This paper proposes a method for estimating nonparametrically the dynamic part of the TV-FRF from known input, noisy output observations. The arbitrary time-variation of the TV-FRF is modelled by Legendre polynomials. In opposition to existing solutions, the proposed method is applicable to arbitrary inputs.