scholarly journals Mathematical model of a measuring complex for determining the external parameters of active phased antenna arrays in the near zone.

2021 ◽  
Author(s):  
V.N. Atrokhov ◽  
◽  
A.V. Litvinov ◽  
S.E. Mishchenko ◽  
V.V. Shatsky ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Field Distribution ◽  
Antenna Arrays ◽  
Phased Array ◽  
Phase Distribution ◽  
Phased Antenna Arrays ◽  
Measuring Complex ◽  
Proposed Model ◽  
Near Zone ◽  
Electrodynamic Modeling

When measuring characteristics of the modern multi-element active phased antenna arrays amplifications method may have problems processing the results of measurements, due to the complexity of the exact adjustment of the overall active phased array, the fluctuations of the parameters of microwave amplifiers, the failure of individual elements, the inadmissibility of the full radiation of aperture antennas in an anechoic chamber. Electrodynamic modeling of active phased array antennas in specialized programs usually requires very large computational costs and it is very difficult to take into account fluctuations in parameters and failures of active phased array elements. In this regard, a mathematical model of the measuring complex is proposed for estimating the field distribution in the near zone of vibratory antenna arrays and generating radiation patterns. The estimation methodology is based on direct measurements of the amplitude-phase distribution of the field of the antenna system on the selected surface in the immediate vicinity of its aperture using a sounding antenna. The main relations for the model are the well-known expressions for calculating the field distribution in the near zone of a vertical symmetrical vibrator, the method of induced electromotive force, and matrix relations for converting the field into various coordinate systems. The model of the measuring complex is used to evaluate the characteristics of the active phased array in the near and far zones. However, it can be used to check real experimental data, taking into account fluctuations in the parameters of the amplitude-phase distribution in the aperture, and failures of antenna elements. The conducted research has shown a good agreement between the calculated characteristics of the active phased array using the proposed model and the aperture method. The time for calculating the antenna directivity characteristics in the proposed model is 30 minutes. The main time is associated with the addition of resistance matrices with elements related to each new position of the probe antenna. However, this time is not comparable to the time required to implement the measurement model in specialized electrodynamic modeling packages.

scholarly journals Features of excitation reconstruction in flat multielement phased antenna array face using dynamic directional patterns

2017 ◽  
pp. 32-39
Author(s):  
S. E. Gavrilova ◽  
A. N. Gribanov ◽  
G. F. Moseychuk ◽  
A. I. Sinani
Keyword(s):  
Antenna Arrays ◽  
High Efficiency ◽  
Phase Distribution ◽  
Radiation Patterns ◽  
Phased Array Antennas ◽  
Phased Antenna Arrays ◽  
Phased Antenna Array ◽  
Transformation Algorithms ◽  
Computational Resources ◽  
Research Show

The study focuses on reconstructing the amplitude-phase distribution of flat multielement passive and active phased antenna arrays with the use of dynamic radiation patterns, measured with electronical scanning without mechanical rotations and antenna movements. The paper describes the measurement settings of dynamic radiation patterns, necessary for reconstructing the amplitude-phase distribution. Findings of the research show that to reconstruct the amplitude-phase distribution according to dynamic radiation diagrams, there is no need for increased computational resources due to the use of Fourier transformation algorithms. After the method was experimentally verified on the specific samples of active phased antenna arrays, its high efficiency was established. The paper gives the examples of reconstructing the amplitude-phase distribution from dynamic radiation patterns in the presence of malfunctions in active phased array antennas.

Automated imitating-measuring complex for designing and measuring characteristics of phased antenna arrays

2011 ◽  
Vol 54 (5) ◽  
pp. 268-273
Author(s):  
V. Usin ◽  
V. Markov ◽  
S. Pomazanov ◽  
A. Usina ◽  
A. Filonenko
Keyword(s):  
Antenna Arrays ◽  
Phased Antenna Arrays ◽  
Measuring Complex

scholarly journals DIAGNOSTICS OF HEADLIGHTS FROM NEAR AREA ON PLACE OF BASING

2020 ◽  
Vol 3 (61) ◽  
pp. 124-127
Author(s):  
O. Besova ◽  
V. Karlov ◽  
O. Lukashuk ◽  
I. Petryshenko
Keyword(s):  
Antenna Array ◽  
Phased Array ◽  
Phase Distribution ◽  
Near Field ◽  
Operating Time ◽  
Array Antenna ◽  
Phased Array Antenna ◽  
Phased Antenna Array ◽  
Near Zone ◽  
Microwave Diagnostics

Methods of microwave diagnostics of a phased array allow reconstructing the amplitude-phase distribution in the antenna and implement on this basis methods for adapting the lattice control to those found in the amplitude-phase distribution to defects. The methods of microwave diagnostics from the near zone described in the well-known literature are realizable only in anechoic chambers or on specially equipped training grounds. To solve the problems of adapting a phased antenna array to a technical state and increasing its operating time under extreme conditions, it is necessary to have methods of integrated microwave diagnostics of a phased antenna array at its location. The aim of the article is to develop a method for microwave diagnostics of a phased array antenna, implemented from the near zone of the antenna at its location, and eliminating the influence of echo signals (ES) on the diagnostic results. The article proposes a method for microwave diagnostics of a phased array antenna from the near field, which allows to exclude the influence on the accuracy of diagnostics of the echo signal present at the measuring site and errors in the positioning of the measuring probe. The proposed method will make it possible to implement microwave diagnostics of the antenna from the near field at its location. The results of microwave diagnostics are supposed to be used to implement various methods of adapting a phased array to a technical condition, significantly increasing its life

scholarly journals Printed broadband dipole for phased array antenna

2020 ◽  
pp. 38-45
Author(s):  
A. S. Razumikhin ◽  
G. N. Devyatkov ◽  
K. A. Laiko ◽  
J. O. Filimonova
Keyword(s):  
Equivalent Circuit ◽  
Frequency Band ◽  
Antenna Arrays ◽  
Phased Array ◽  
Dielectric Substrate ◽  
Array Antenna ◽  
Electromagnetic Modeling ◽  
Phased Array Antenna ◽  
Phased Antenna Arrays ◽  
Directivity Characteristics

The article discusses ways to increase the operating frequency band of a symmetrical broadband vibrator in printed version for a phased array antenna. The equivalent circuit of such an emitter is described. Various designs of an emitter made on a Rogers RT5880 dielectric substrate with a thickness of t = 1.5 mm and εr = 2.2 and the results of electromagnetic modeling are considered. A wide working band is achieved due to the introduction of a dual-circuit system and a modified geometry of the vibrator arms. Topologies, as well as matching and directivity characteristics of three types of antennas are given. The developed antenna is intended for use in broadband systems both as a separate independent antenna and as a radiator for digital phased antenna arrays. The CST Microwave studio environment was used to simulate the emitter.

scholarly journals Microwave phased array for aerological radar

2019 ◽  
Vol 30 ◽  
pp. 05022
Author(s):  
Sergey Shabunin ◽  
Sergey Plokhov ◽  
Ilia Bukrin ◽  
Victor Chechetkin
Keyword(s):  
Antenna Arrays ◽  
Phased Array ◽  
Radio Channel ◽  
Phase Shifters ◽  
Operating Conditions ◽  
Design Environment ◽  
Phased Array Antenna ◽  
Radar Station ◽  
Phased Antenna Arrays ◽  
Angular Velocities

The use of radars with phased antenna arrays in aerological atmospheric sounding systems significantly increases the technical characteristics of the radio channel, ensures reliable auto-tracking in the near zone at high angular velocities of the aerological probe, and reduces the overall dimensions of the radar station. Modelling and optimization of the parameters of the phased array and phase shifters were carried out in the NI AWR Design Environment. The results of the study showed that when designing a radar station, it is possible to reduce the level of side lobes of the phased array antenna pattern and the effect of reflections from the underlying surface under operating conditions significantly.

scholarly journals A method for measuring dynamic radiation patterns of passive and active phased antenna arrays

2016 ◽  
pp. 32-40
Author(s):  
A. N. Gribanov ◽  
S. E. Gavrilova ◽  
A. E. Dorofeev ◽  
G. F. Moseychuk ◽  
O. S. Alekseev
Keyword(s):  
Radiation Pattern ◽  
Cross Sections ◽  
Antenna Arrays ◽  
Phase Distribution ◽  
Sampling Theorem ◽  
Joint Stock Company ◽  
Radiation Patterns ◽  
Stock Company ◽  
Phased Antenna Arrays ◽  
Time Required

The study deals with a method for measuring dynamic radiation patterns of phased antenna arrays and active phased antenna arrays. The method consists of measuring the signal during electronically scanning the beam of a static antenna. We show the main differences between dynamic and static radiation patterns. The Whittaker Nyquist – Kotelnikov – Shannon sampling theorem forms the basis of our recommendations for selecting the number of measurement points in the case of a dynamic radiation pattern. We supply a diagram of a work station dedicated to measuring dynamic radiation patterns using the workbench developed by the Joint-stock company “V. Tikhomirov Scientific Research Institute of Instrument Design”. We present measured static and dynamic radiation patterns of a real-world active phased antenna array.Our method for measuring dynamic radiation patterns significantly decreases the time required for determining radiation characteristics of phased antenna arrays and active phased antenna arrays for separate angular cross-sections and over the whole visibility scope, and increases their information content. Moreover, measuring dynamic radiation patterns does not require a rotating workbench. It is possible to use dynamic radiation pattern to determine static (as measured by turning the antenna) far-field patterns, to restore electric current magnitude and phase distribution over the aperture and to troubleshoot the antenna.

scholarly journals Development of small-sized phased antenna arrays on ferrite phase shifters for unmanned aerial vehicles

2020 ◽  
pp. 19-25
Author(s):  
S. S. Bushkin ◽  
S. A. Golovin ◽  
N. N. Soroka
Keyword(s):  
Unmanned Aerial Vehicle ◽  
Antenna Arrays ◽  
Phased Array ◽  
Phase Shifters ◽  
Array Antenna ◽  
Ferrite Phase ◽  
Phased Array Antenna ◽  
Radiation Characteristics ◽  
Phased Antenna Arrays ◽  
Aerial Vehicle

In this paper, an approach to the development of small-sized phased antenna arrays on ferrite phase shifters is considered. The paper presents examples of predicting the radiation characteristics of phased antenna arrays and processing their measured characteristics using mathematical models. On the basis of a phased array antenna for an unmanned aerial vehicle, the influence of the design features of such an antenna on its radiation characteristics is shown. The radiation characteristics of a phased array antenna for an unmanned aerial vehicle developed at V. V. Tikhomirov Scientific Research Institute of Instrument Design are presented.

THE DEVELOPMENT OF THE MATHEMATICAL MODEL OF PREDICTING THE INDICATORS OF ACCREDITATION OF TECHNICAL UNIVERSITIES IN THE RUSSIAN FEDERATION

2017 ◽  
pp. 27-38
Author(s):  
Olga Mikhaylovna Tikhonova ◽  
Alexander Fedorovich Rezchikov ◽  
Vladimir Andreevich Ivashchenko ◽  
Vadim Alekseevich Kushnikov
Keyword(s):  
Mathematical Model ◽  
System Dynamics ◽  
Regression Model ◽  
Oriented Graph ◽  
Real Data ◽  
Educational Process ◽  
Proposed Model ◽  
Linear Differential ◽  
The University ◽  
The Mathematical Model

The paper presents the system of predicting the indicators of accreditation of technical universities based on J. Forrester mechanism of system dynamics. According to analysis of cause-and-effect relationships between selected variables of the system (indicators of accreditation of the university) there was built the oriented graph. The complex of mathematical models developed to control the quality of training engineers in Russian higher educational institutions is based on this graph. The article presents an algorithm for constructing a model using one of the simulated variables as an example. The model is a system of non-linear differential equations, the modelling characteristics of the educational process being determined according to the solution of this system. The proposed algorithm for calculating these indicators is based on the system dynamics model and the regression model. The mathematical model is constructed on the basis of the model of system dynamics, which is further tested for compliance with real data using the regression model. The regression model is built on the available statistical data accumulated during the period of the university's work. The proposed approach is aimed at solving complex problems of managing the educational process in universities. The structure of the proposed model repeats the structure of cause-effect relationships in the system, and also provides the person responsible for managing quality control with the ability to quickly and adequately assess the performance of the system.

A Mathematical Model for the Anaerobic Digestion Process Applied to a Mixture of Night Soil and Septic Tank Sludge

1986 ◽  
Vol 18 (7-8) ◽  
pp. 239-248 ◽  
Author(s):  
Sung Ryong Ha ◽  
Dwang Ho Lee ◽  
Sang Eun Lee
Keyword(s):  
Mathematical Model ◽  
Anaerobic Digestion ◽  
Biomass Concentration ◽  
Gas Production ◽  
Septic Tank ◽  
Volatile Acid ◽  
Hydraulic Residence Time ◽  
Anaerobic Digestion Process ◽  
Digestion Process ◽  
Proposed Model

Laboratory scale experiments were conducted to develop a mathematical model for the anaerobic digestion of a mixture of night soil and septic tank sludge. The optimum mixing ratio by volume between night soil and septic tank sludge was found to be 7:3. Due to the high solids content in the influent waste, mixed-liquor volatile suspended solids (MLVSS) was not considered to be a proper parameter for biomass concentration, therefore, the active biomass concentration was estimated based on deoxyribonucleic acid (DNA) concentration in the reactor. The weight ratio between acidogenic bacteria and methanogenic bacteria in the mixed culture of a well-operated anaerobic digester was approximately 3:2. The proposed model indicates that the amount of volatile acid produced and the gas production rate can be expressed as a function of hydraulic residence time (HRT). The kinetic constants of the two phases of the anaerobic digestion process were determined, and a computer was used to simulate results using the proposed model for the various operating parameters, such as BOD5 and volatile acid concentrations in effluent, biomass concentrations and gas production rates. These were consistent with the experimental data.

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