Vol 22, No 1 (2019)
- Year: 2019
- Articles: 10
- URL: https://journals.ssau.ru/pwp/issue/view/355
Articles
Influence of the particle size distribution on the characteristics of a four-wave radiation converter in a transparent two-component medium
Abstract
The characteristics of the four-wave radiation converter in a transparent liquid have been analyzed with considering the normal size distribution of nanoparticles contained in it. Shown that in the dependences of the amplitude reflection coefficient and the output time of the band half-width of spatial frequencies cut out by such a radiation converter to steady-state value from dispersion there are extremes at which the reflection coefficient takes the greatest value and the output time takes the smallest value.
4-9
The numerical analysis of E-polarizied electromagnetic wave reflections from inhomogeneous dielectric layer
Abstract
The work is devoted to the electromagnetic analysis of metamaterial based on a dielectric layer having inhomogeneous atoms distribution along the transverse coordinate. The paper considers the solution of a two-point boundary value problem of the plane linearly polarized electromagnetic wave reflection from an inhomogeneous dielectric layer. High-speed algorithm of electromagnetic wave reflection and transmission characteristics calculating based on solving a two-point boundary value problem is proposed. The frequency dependences of the reflection coefficients modulus are calculated for different real part of the complex permittivity inhomogeneous profiles at various incidence angles. It is shown that in the region of the lower normalized frequency range a dielectric layer with a parabolic profile has less reflection than a dielectric layer with a linear refractive index profile.
10-15
16-20
On some integrals of products of cylindrical functions
Abstract
For a number of solutions to problems of a multilayer optical fiber, the field of which in each layer is described by the sum of the corresponding Bessel functions, integrals of the products of these functions are of interest. Unfortunately, not all of these integrals are presented in the literature in integral tables in explicit form. In the proposed work an attempt was made to fill this gap.
21-25
Eigenvalues of integral operator of the singular integral equation for a thin tubular vibrator antenna
Abstract
The singular integral equation of a thin tubular vibrator is considered. This paper analyzed the dependence of the eigenvalues of the integral operator of the singular integral equation on the frequency and geometric dimensions of the vibrator with the determination of their asymptotic behavior at small lengths and small radii of the vibrator. It is shown that these dependences admit a simple polynomial approximation, and it is shown that an approximation in harmonic functions can be used for the eigenfunctions of an integral operator. Results can be used as the basis for constructing a approximate solutions of current on the tubular vibrator.
26-31
The discrete biharmonic model of Thomson self-oscillators
Abstract
For modeling of self-oscillations in generators of Thomson type the numerical-analytic method is offered. The method is based on representation of self-oscillatory system in the form of set of two oscillators - the main frequency and its third harmonica. The leading oscillator generates strictly monochromatic self-oscillations in discrete time and excites on the oscillator of the third harmonica. The main attention is paid to self-oscillations in three-point schemes with capacitor and inductive communications. It is shown that the offered method of modeling allows to give comparative estimates of amplitudes of harmonious components of a spectrum of self-oscillations.
32-35
To the matter of improving the efficiency of communication channels with moving objects using APSK-n-signals
Abstract
The features of the functioning of a non-parametric, frequency-selective communication channel with intersymbol interference are analyzed, in which APSK- N -signal for data transmission is used. The stability of data transfer rate increasing in such channel using proposed approach based on the «transparency windows» utilizing is studied. In this study the equally probable law of symbol values in modulating sequence was used. The stability «transparency windows» in the presence of a destabilizing factor as a frequency detuning is estimated. In addition, the influence on the stability of the «transparency window” of measurement errors of the envelope and phase produced by the receiver has been evaluated. Based on the study, recommendations were made to improve the speed in such communication channels.
36-49
Application of the theory of bifurcations to the analysis of the stability of impulse voltage stabilizers of a rising type
Abstract
This article discusses the application of the theory of bifurcation to pulsed voltage up-stabilizers, studied its behavior, and analyzed the stability conditions for varying various parameters of the system. Also obtained are surfaces of stability of pulsed voltage up-regulators with varying various system parameters.
50-56
Electrophysical and optical properties of the silicon carbide device structures
Abstract
The results of the research of silicon carbide thin films obtained by high-frequency magnetron sputtering on various types substrates are presented. The surface morphology of silicon carbide was studied by scanning electron microscopy. Surface roughness was measured using a profilometer. The phase composition and structural perfection of the films were determined by x-ray phase analysis and Raman scattering. The method of silicon carbide layers optical parameters calculation based on experimentally obtained spectra of natural light normal reflection from the structure and from the substrate is developed. The refractive index, extinction coefficient and specific conductivity of silicon carbide films are calculated depending on the wavelength of the incident light.
57-66
The concept of a glocal-integrated infrastructure of spatial and territorial development as the basis of the General scheme for the development of communication networks of the Russian Federation in the framework of the action plan for the «Information infrastructure» program of the «Digital economy of the Russian Federation»
Abstract
The article highlights the concept of a glocal-integrated infrastructure of spatial and territorial development as the basis of the General scheme for the development of communication networks of the Russian Federation as part of the action plan for the «Information infrastructure» program of the «Digital economy of the Russian Federation».
67-79
Регистрационный номер и дата принятия решения о регистрации СМИ: серия ФС 77 - 68199 от 27.12.2016.