Theoretical principles for determination of instantaneous impedance spectra
were formulated. Coupling of the pseudo-white noise and short-time Fourier
transformation methods allows determination of impedance spectra changes a
s the function of time. The theoretical principles of the new measurement m
ethod indicate the possibility of conducting impedance investigations of no
n-stationary processes. The frequency resolution and time selection of the
total time-frequency analysis of impedance spectra depend on the choice of
the size of the Gaussian window. (C) 2000 Elsevier Science S.A. All rights
reserved.