A mathematical technology for digital processing of geophysical signals has been developed for estimating non-stationary parametric functions. Two-stage approximations with local models in the first stage and weighted approximation averaging models in the second stage were used. Algorithms for calculating estimates of parametric amplitude and frequency functions, increment/decrement functions, and frequency dispersions have been developed. Error formulas for estimating parametric pulsation functions have been proposed. Examples of applying the technology to model and experimental observations have been implemented. The technology's capabilities are demonstrated, allowing for the calculation of frequency function estimates and frequency derivative functions for geomagnetic pulsations of the “pearl” type.
Getmanov et al. (2026) studied this question.