# Tag Archives: communication

THE SIMULATION AND ALGORITHMIC SOLUTIONS OF PROBLEMS IN WIRELESS
COMMUNICATION SYSTEMS IN THE CONDITIONS OF CLOSED SPACES

UDC 621.396

D. P. Komaritiy, Y. S. Sakharov

The urgency of research is caused by that in modern conditions there is a widespread use of wireless networks. When designing wireless networks, a big role for the modeling stage, which includes the calculations of the basic parameters of wireless access systems. In this regard, this paper aims to identify opportunities to use appropriate approaches in modeling the propagation of radio signals in indoor environments, and at identifying possible errors in calculations. A leading approach to the study of this problem is the use of ray tracing technique, which allows to take into account the different geometry of the premises and materials located within the facilities. The article presents the results of simulation program Wireless InSite. The materials of the paper are of practical value to professionals associated with the design of wireless networks indoors.

Keywords: communication, simulation, wireless networks, algorithm, area.

Full text:
KomaristySacharov_3_1_17.pdf

THE SIMULATION IN THE TIME DOMAIN FOR SCATTERING OF RADIO WAVES ON THE OBJECT LOCATED UNDER THE GROUND COVER

UDC 621.396

V.N. Kostrova, E.A.Rybalchenko

The paper discusses an analytical solution in the time domain Pocklington equation for a straight thin wire of finite length under land cover at a certain depth. This wire is excited by an electromagnetic wave. The description of the transition surface to air is carried out on a simplified model for the reflection coefficient. The analytical solution is based on the use of Laplace transform and Cauchy’s theorem. The results of numerical calculations of the excited current in the time domain for different parameters – the conductivity of the medium are given. Recommendations on the use of the method of parallel computing to accelerate numerical solution of the problem are shown.

Keywords: communication, scattering of electromagnetic waves simulation in time domain integral equations.

Full text:
KostrovaRibalchenko_4_16_1.pdf

THE SIMULATION OF RADIO WAVE SCATTERING ON TWO DIMENSIONAL CYLINDERS

UDC 621.396

V.N. Kostrova, E.A.Rybalchenko

We apply principles of superposition for analysis of normal of plane waves incident on an infinitely long conducting or dielectric circular cylinders with multilayer coatings made of materials with magneto-minimize or maximize the radar cross section (RCS). We consider the case of TE and TM polarizations of the incident wave. Optimization of RCS by the method of least squares leads to the determination of layer thickness and material with the complex values of the magnetic and dielectric permeability is carried out. Also the analysis of sensitivity of RCS with given geometric parameters and material parameters for a conducting cylinder coated with a magneto is given.

Keywords: communication, electromagnetic wave scattering, integral equations, cylinder.

Full text:
KostrovaRibalchenko_3_16_2.pdf

THE ANALYSIS OF THE COVERAGE IN COMMUNICATION SYSTEMS BASED ON GEOMETRICAL ALGORITHMS

UDC 621.396

A. P. Preobrazhensky

This paper discusses the issues related to improvement of radio coverage in the communication systems. It is proposed to reduce this problem to geometric to analyze whether a given point to the polygon, where the polygon represents the coverage area of certain base station. We consider several algorithms. In the method of ray tracing produced by a ray of given points in certain directions and counting the number of times the beam is the intersection of edges of the polygon. Also considered trigonometric algorithm when the points hold the rays for all the vertices of the polygons. The analysis rpm which is oriented boundary of the polygon around a point.

Keywords: communication, radio coverage, algorithm, base station, polygon, approximation.

Full text:
Preobrazhensky_2_16_3.pdf

THE ANALYSIS OF ELECTROMAGNETIC WAVE PROPAGATION INSIDE THE BUILDING WITHIN THE RADIAL APPROACH

UDC 621.396

A. P. Preobrazhensky

In this paper the analysis of the characteristics of radiation methods for the analysis of electromagnetic wave propagation – the method of geometrical optics, physical optics, physical theory of diffraction are considered. In order to determine the amplitude of the field in each point of space is required to determine all the rays that pass through this point. The considered model of distribution of the main beam in the room for two cases – floor reflections and the reflection from the object, located a certain height above the floor. Built according to the horizontal distance to the point of reflection of the beam on the incidence angle, the height of the receiver from the angle of reflection, the height of the receiver for various values of height of the reflecting object.

Keywords: simulation, communication, diffraction, wave propagation in indoor radiation methods.

Full text:
Preobrazhensky_2_16_2.pdf

THE SIMULATION OF SCATTERING CHARACTERISTICS OF OBJECTS HAVING EDGES

UDC 621.396

A. P. Preobrazhensky

In the paper the problems of scattering of radio waves on the objects, which include edge are considered. First, the analysis of the simplest edges, which is a wedge-shaped structure having a certain angle of solution is given. For the general case the edge of such structures may be truncated. The calculations of the scattering parameters was based on the method of integral equations in the framework of the Kirchhoff approximation. The examples of calculations of scattering characteristics are given, and built the radio image. Further the models of hollow structures is considered. The edges of these hollow structures can be defined by different edges. The calculations of the scattering parameters was based on the method of integral equations. The examples of calculations of scattering characteristics of hollow structures, and built the radio image of the edge part of the hollow structure.

Keywords: simulation, communication, diffraction, wave propagation, design, edge, hollow structure.

Full text:
Preobrazhensky_2_16_1.pdf

THE POSSIBILITY OF USING ITERATIVE METHOD FOR THE CALCULATIONS OF SCATTERING CHARACTERISTICS OF COMBINED OBJECTS

UDC 621.396

A. G. Yurochkin, A.V.Danilova, I.A.Gusarova

This paper considers the scattering of radio waves on the combined object consisting of several components. One of the possible ways, which is analyzed by the application of the method of integral equations. But with a large size of circuits and an increase in the number of components the time required for calculations increases significantly. In this regard, the iterative method is considered, which takes into account only the currents that are related directly to the reflection between components, which leads to a reduction in the size of the matrix of linear equations and an overall reduction in the computation time. Given an example, when as a combined object is a combination of two-dimensional elliptic cylinders. Characteristic size at which the iterative method works well.

Keywords: communication, diffraction, wave propagation, method of integral equations, iteration, cylinder.

Full text:
YurochkinDanilovaGusarova_2_16_2.pdf

THE ANALYSIS OF APPROXIMATE MODELS FOR ESTIMATING THE AVERAGE CHARACTERISTICS OF THE SCATTERING DIFFRACTIVE STRUCTURE

UDC 621.396

A. G. Yurochkin, A.V.Danilova, I.A.Gusarova

This paper analyses the possibilities of how to apply the approximate model in order to assess the average characteristics of the scattering object. The exact approach is based on the method of integral equations, and an approximate model based on the combination of the method of edge waves and the physical optics approximation. The object is represented in the form of separate components. It is shown how the defined sector angles, given the framework of specific errors. Based on how aggregated information on the elements of an object given suggestions on how to build a subsystem of CAD in order to design the average characteristics of the objects. As a test data for the subsystem are selected dimensions of the elements and sector angles, the required levels for the average characteristics of the scattering.

Keywords: communication, diffraction, wave propagation, design, CAD, diffraction structure.

Full text:
YurochkinDanilovaGusarova_2_16_1.pdf

THE PREDICTION OF THE SCATTERING CHARACTERISTICS OF METAL PYRAMIDS IN THE FREQUENCY RANGE BASED ON THE USE OF GENETIC ALGORITHM

UDC 621.396

A. A. Maksimova, V. N. Kostrova, A. A. Androsov

The analysis model of prediction of radar characteristics is conducting pyramid in the frequency range on the basis of experimental evidence, what is its scattering properties is given. For the case of a vertically incident plane electromagnetic wave using the method of integral equations by numerical way, the calculation of the angular dependences for radar cross section of the pyramid, as well as with the involvement of a genetic algorithm made a prediction of RCS for the specified object in the frequency range is carried out.

Keywords: communication, radio waves, forecasting, optimization, genetic algorithm, integral equations, objects with complex shape.

Full text:
MaximovaKostrovaAndrosov_2_16_2.pdf

OPTIMIZATION OF WIRELESS COMMUNICATION NETWORKS BASED ON ARTIFICIAL INTELLIGENCE METHODS

UDC 621.396

A. A. Maksimova, V. N. Kostrova, A. A. Androsov

The analysis of the approaches designed for the estimation of scattering characteristics of diffractive structures and parameters of wireless communication systems is given. The possibility of optimizing wireless communication systems in the room based on artificial intelligence methods (genetic algorithm) is considered. As the main calculation method is proposed to use the ray-tracing method and an optimization technique – genetic algorithm. In a genetic algorithm it is proposed to use single point crossing-over, defined by its steps. As chromosomes the coordinates of the mesh around the point observations made at a given step are considered. A combined algorithm of calculating the optimal location of access points inside the building is proposed. The results of pre-test calculations are recorded.

Keywords: wireless communication, optimization, communication, radiowave propagation, ray method.

Full text:
MaximovaKostrovaAndrosov_2_16_1.pdf