Artificial time series. The frequency characteristic of the artificial time series used for the validation of the presented method. It consists of three parts. The first part is a harmonic oscillation at 15 Hz. The second part is a linear chirp which starts at a frequency of 15 Hz and ends at a frequency of 10 Hz. The duration of the chirp is uniformly distributed between 50 and 450 ms. The third part is a harmonic oscillation at a frequency of 10 Hz with an uniformly distributed phasing.