NONSTATIONARY IMPEDANCE SPECTROSCOPY - MATHEMATICAL BASIS

The problem of nonstationary impedance analysis has been examined from a general point Of view. A rigorous definition of the concept of the instantaneous impedance has been given. Two principal approaches to th e solution of the problem of instantaneous analysis have been presente d. An evolutionary approximation has been based on the assumption that Fourier transformation is effective and leads to four-dimensional ana lysis. An exact solution has been realized with the aid of the novel m athematical theory of rotating Fourier transformations, which make it possible to give estimates of the instantaneous values of the signals being analyzed. The importance of the development of the theory of the instantaneous impedance has been demonstrated.