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Annotation - The estimation of the spectral mode of the photometric signal reflected from a space object (SO) by the two-sided Prony method is considered. The purpose of the work is to improve the quality of the spectral analysis of multi-frequency light reflections from SO using a short sample of observations. A criterion for the effectiveness of the proposed methodology is proposed to use the minimization of the relative deviations AF of the estimated flicker frequencies $\tilde{F}$ from the true frequencies $F$ for the two-sided Prony least square method and the autoregressive method (AR) of spectral analysis.

The article proposes a method for the coefficients reconstruction of a discrete autocorrelation function of random signals with a unimodal power spectral density to construct their parametric models. The method is based on finding the optimal values of the relative width ΔFT and the weighting factor α in [0; 1] of the spectral mode, which characterizes the share of the Gaussian and resonant components in the spectrum envelope. The proposed method makes it possible to reduce by 1.5–4 times the discrepancy between the control and estimated spectra in comparison with the known approaches to parametric spectral analysis. An increase in the adequacy of spectral estimation makes it possible to reduce the length M of the analyzed time sample by a factor of 2.3–4 times, while maintaining the accuracy of the spectral analysis achieved by other known parametric methods. Winnings are achieved by using a priori information about the spectral properties of the analyzed process.

A coordinated physicomathematical model for the propagation of a soliton-like electromagnetic pulse in a heterogeneous medium is developed in the presence of strong discontinuities in the electromagnetic field. The model is based on the reduction of Maxwell’s equations to the well-studied wave equation. When the electromagnetic pulse was specified, its amplitude modulation was taken into account, as was the nonstationary broadening of the spectral line. Conditions for matching the momentum for the first initial boundary-value problem are obtained. The time dispersion of the electrical induction is taken into account in terms of the function of signal conditioning which takes account of the broadening of its spectral line and integration over the continuous spectrum. With this approach, it is not necessary to neglect spatial derivatives, and also to use spatial nonlocal relations to take account of the effect of surface charge, surface current, and spatial dispersion of electrical induction at the interfaces of adjacent media.

We propose a method for estimating the beat frequency of multi-wavelength light reflections from biological tissues using a short (dozens of heartbeats) sequence of observational samples to improve the accuracy of the spectral analysis of photoplethysmographic signals and assess the dynamics of heart contractions. We compare the relative deviation from the true frequency of the estimate obtained by the two-sided Prony least squares method to the estimate obtained using the autoregressive method.

Suppression of clutter and noise is one of the most important problems of radio location signals processing. It is shown proposed algorithm of division of processing vector into sub-vectors of non-recursive noise suppression filter allows to increase average by signals Doppler velocities probability of correct detection on 6–28% in compare to known non-adaptive whitening filter. Proposed algorithm does not require the noise correlation matrix inversion in case of modification of power of clutter noise that reduces computational burden 1.8–7 times on its realization in compare to optimal adaptive algorithm.

This work aims to modify the structure of frequency-multichannel filter for processing fluctuating signals with staggered period, analyze the efficiency of the modified filter and estimate additional computational costs required for its implementation in comparison with frequency-multichannel filter based on the fast Fourier transform (FFT). We also consider the issues involved in simplification of modeling random staggered-period signals by means of the parallel structure of autoregressive filters.

It is proposed and investigated a method for linear autoregressive models of radio-reflections optimization, based on procedure of autoregression vector coefficients weighting by modifying factor. It is shown, that proposed method allows computational shortcut for construction of overdetermined autoregressive models of radio-reflections up to 2–4 times by excluding multiplication procedure of rectangular correlation matrix of modeled process in overdeterminated linear equation systems.