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Tytuł:
Effect of micro protrusions on the performance of elliptical journal bearings operating with couple stress lubricant
Autorzy:
Abass, Basim Ajeel
Mahdi, Mushrek A.
Powiązania:
https://bibliotekanauki.pl/articles/1840900.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
Tematy:
elliptical journal bearing
hydrodynamic lubrication
micro-protrusions
couple-stress lubricant
non-Newtonian fluids
smarowanie hydrodynamiczne
płyny nienewtonowskie
Opis:
Elliptical bearing is characterized by low induced temperature and high stability at higher speed in comparison with the cylindrical journal bearing. The performance of such bearings can be affected by the type of oil used and its surface properties. The main goal of this work is to study the surface micro protrusion effect on the steady state operation of elliptical journal bearing lubricated with couple stress lubricant. The modified Reynolds’ equation to take into account the effects of couple stress lubricant and micro protrusions of the bearing surfaces is solved using finite difference method. The governing equations were solved using a prepared FORTRAN computer program. Pressure distribution, load carrying capacity and coefficient of friction have been studied for a bearing in laminar flow regime. The mathematical model was validated by comparing pressure results for the elliptical bearing of the present work with that obtained by Hussain et al.(1996). The obtained results demonstrate that the lubricant pressure and the load carried by the bearing decrease for the bearing with higher ellipticity factor while the load carried by the bearing increases for the bearing with higher protrusions or when using a couple stress fluid with higher couple stress variable.
Źródło:
Diagnostyka; 2021, 22, 2; 97-104
1641-6414
2449-5220
Pojawia się w:
Diagnostyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Microarray-core based circular photonic crystal fiber for high chemical sensing capacity with low confinement loss
Autorzy:
Asaduzzaman, S.
Ahmed, K.
Powiązania:
https://bibliotekanauki.pl/articles/174575.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
circular photonic crystal fiber
confinement loss
elliptical core
chemical sensor
relative sensitivity
Opis:
In this article, a circular photonic crystal fiber based chemical sensor has been presented where core region is designed with an array of elliptical holes. The proposed structure is numerically investigated by using a full vectorial finite element method. From the numerical results, it is observed that introducing an array of elliptical holes helps to obtain the high relative sensitivity and realizes a low confinement loss. In addition, the increase in the value of the diameter of holes in the innermost ring enhances the relative sensitivity. Moreover, the increase in the value of the diameter of holes in the outermost ring reduces the confinement loss. In this work, we have considered an industrially valuable chemical ethanol. Simulation results disclose that the highest relative sensitivity of proposed photonic crystal fiber is 29.25% for ethanol and the confinement loss is 7.68 × 10–7 dB/m at the wavelength 1.5 µm.
Źródło:
Optica Applicata; 2017, 47, 1; 41-49
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spatial construction of intersection points of two ellipses
Przestrzenna konstrukcja wspólnych punktów dwóch elips
Autorzy:
Bieliński, A.
Łapińska, C.
Powiązania:
https://bibliotekanauki.pl/articles/973250.pdf
Data publikacji:
2006
Wydawca:
Polskie Towarzystwo Geometrii i Grafiki Inżynierskiej
Tematy:
ellipse
elliptical cone
affinity
elipsa
stożek eliptyczny
pokrewieństwo
Opis:
A spatial construction of intersection points of two coplanar ellipses, whose major axes lie on the same line and minor axes are equal in length, is given.
Rozpad linii przenikania dwóch walców został tu wykorzystany do wyznaczenia punktów przecięcia się dwóch elips będących w określonym szczególnym położeniu – elipsy leżą w jednej płaszczyźnie, ich duże osie leżą na jednej prostej i częściowo pokrywają się, ich małe osie są równej długości.
Źródło:
Journal Biuletyn of Polish Society for Geometry and Engineering Graphics; 2006, 16; 17-19
1644-9363
Pojawia się w:
Journal Biuletyn of Polish Society for Geometry and Engineering Graphics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design of a Microstrip Filtering Antenna for 4G and 5G Wireless Networks
Autorzy:
Boddu, Ramesh
Deb, Arindam
Roy, Jibendu Sekhar
Powiązania:
https://bibliotekanauki.pl/articles/24200731.pdf
Data publikacji:
2023
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
elliptical microstrip patch antenna
filtering antenna
hairpin bandpass filter
Opis:
The filtering antenna provides both radiation and filtering features and is an important component for the RF front-end of wireless devices. The main function of a filtering antenna is to reject out-of-band signals, thus reducing the interference from adjacent channels. The aim of the present work is to design a 2.6 GHz microstrip filtering antenna for 4G and 5G global mobile services. The filtering antenna is designed using a hairpin bandpass filter integrated with an elliptical microstrip aerial. Good impedance matching is obtained by using appropriate dimensions of the hairpin bandpass filter. The 10 dB return loss bandwidth of the filtering antenna is approx. 5.7%, with the maximum gain for the elliptical filtering antenna of approx. 2.2 dB. Good agreements between the measured and simulated results are obtained for the proposed filtering antenna and the bandwidth covers almost the entire 2.6 GHz band.
Źródło:
Journal of Telecommunications and Information Technology; 2023, 2; 78--83
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Rayleigh number on internal eccentricity in a heated horizontal elliptical cylinder to its coaxial square enclosure
Autorzy:
Bouras, Abdelkrim
Taloub, Djedid
Driss, Zied
Powiązania:
https://bibliotekanauki.pl/articles/1839785.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
konwekcja naturalna
płyn Newtona
liczba Rayleigha
natural convection
newtonian fluid
geometry ratio
Rayleigh number
elliptical cylinder
Opis:
This paper deals with numerical investigation of a natural convective flow in a horizontal annular space between a heated square inner cylinder and a cold elliptical outer cylinder with a Newtonian fluid. Uniform temperatures are imposed along walls of the enclosure. The governing equations of the problem were solved numerically by the commercial code Fluent, based on the finite volume method and the Boussinesq approximation. The effects of Geometry Ratio GR and Rayleigh numbers on fluid flow and heat transfer performance are investigated. The Rayleigh number is varied from 103 to 106. Throughout the study the relevant results are presented in terms of isotherms, and streamlines. From the results, we found that the increase in the Geometry Ratio B leads to an increase of the heat transfer coefficient. The heat transfer rate in the annulus is translated in terms of the average Nusselt numbers along the enclosure's sides. Tecplot 7 program was used to plot the curves which cleared these relations and isotherms and streamlines which illustrate the behavior of air through the channel and its variation with other parameters. The results for the streamlines, isotherms, local and average Nusselt numbers average Nusselt numbers are compared with previous works and show good agreement.
Źródło:
International Journal of Applied Mechanics and Engineering; 2020, 25, 3; 17-29
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Heat transfer by natural convection from a heated square inner cylinder to its elliptical outer enclosure utilizing nanofluids
Autorzy:
Bouras, Abdelkrim
Taloub, Djedid
Driss, Zied
Debka, Siham
Powiązania:
https://bibliotekanauki.pl/articles/2174195.pdf
Data publikacji:
2022
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
konwekcja naturalna
nanociecz
ułamek objętościowy
natural convection
Rayleigh number
nanofluid
volume fraction
square elliptical
Opis:
In this paper a numerical study of natural convection of stationary laminar heat transfers in a horizontal ring between a heated square inner cylinder and a cold elliptical outer cylinder is presented. A Cu-water nanofluid flows through this annular space. Different values of the Rayleigh number and volume fraction of nanoparticles are studied. The system of equations governing the problem was solved numerically by the fluent calculation code based on the finite volume method and on the Boussinesq approximation. The interior and exterior surfaces are kept at constant temperature. The study is carried out for Rayleigh numbers ranging from 310 to 510. We have studied the effects of different Rayleigh numbers and volume fraction of nanoparticles on natural convection. The results are presented as isotherms, isocurrents, and local and mean Nusselt numbers. The aim of this study is to study the influence of the thermal Rayleigh number and volume fraction of nanoparticles on the heat transfer rate.
Źródło:
International Journal of Applied Mechanics and Engineering; 2022, 27, 2; 22--34
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Integration of elliptical ship domains and velocity obstacles for ship collision candidate detection
Autorzy:
Chen, P. F.
Van Gelder, P.
Mou, J. M.
Powiązania:
https://bibliotekanauki.pl/articles/116538.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
collision avoidance
elliptical ship domain
ship collision candidate detection
time-discrete velocity obstacle algorithm (TD-NLVO)
AIS Data
ship trajectory
collision candidate detection
collision candidate
Opis:
The maritime shipping industry has been making significant contributions to the development of the regional and global economy. However, maritime accidents and their severe consequences have been posing an incrementing risk to the individuals and societies. It is therefore important to conduct risk analysis on such accidents to support maritime safety management. In this paper, a modified ship collision candidate detection method is proposed as a tool for collision risk analysis in ports and waterways. Time-Discrete Velocity Obstacle algorithm (TD-NLVO) is utilized to detect collision candidates based on the encounter process extracted from AIS data. Ship domain model was further integrated into the algorithm as the criteria for determination. A case study is conducted to illustrate the efficacy of the improved model, and a comparison between the existing method and actual ship trajectories are also performed. The results indicate that with the integration of ship domain, the new method can effectively detect the encounters with significant collision avoidance behaviours. The choice of criteria can have a significant influence on the results of collision candidate detection.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2019, 13, 4; 751-758
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Technical safety of buildings around polish quarries against harmful seismic vibrations caused by rock blasting
Autorzy:
Chrzan, Tadeusz
Sobotka, Jerzy
Powiązania:
https://bibliotekanauki.pl/articles/2201996.pdf
Data publikacji:
2023
Wydawca:
Centrum Rzeczoznawstwa Budowlanego Sp. z o.o.
Tematy:
seismic elliptical distribution of vibrations
building damage
rock blasting
rozkład wstrząsów sejsmicznych
uszkodzenie budynku
wysadzanie skał
Opis:
This paper presents the results of measurements of the elliptical distribution of seismic vibrations generated during rock blasting. The technical safety of a building in the area of seismic vibrations is determined by the vibration velocity that does not exceed the line B included in zone II of the scale of dynamic influences [SWD]. The hypothesis proved in the paper is that for both elliptical and circular distributions of the vibration velocity in rock mining with blasting material [BM] there is a directionality of the horizontal radial component Vx and the tangential component Vy of the vibration velocity. The magnitude of the components Vx and Vy of the vibration velocity at the same distance from the vibration source depends on the directional angle "α" between the line of the blast holes and the line connecting the centre of the surface of the rock block being mined with [BM] and the place of measurement. The elliptical shapes of the graphs Vx and Vy obtained during the mining of the BM of the basalt deposit, which depend on the value of the directional angle, were compared with the shape of the circular velocity graphs Vx and Vy. New correlations are given that take into account the directional angle when calculating the maximum vibration velocity values needed to determine the damage caused to a bulding by the SWD.A dynamic impact scale [SWD] for the assessment of building damage as the vibration velocity acting on the building increases is given and discussed. Vibration velocity diagrams measured during the excavation of BM rock are presented for circular distributions in accordance with theoretical predictions. A vibration velocity diagram for an elliptical distribution, inconsistent with a circular distribution, measured during the excavation of BM rock is presented. It is shown that the directionality of the horizontal radial and tangential components of vibration velocity exists for both circular and elliptical distribution of vibration velocity in rock excavation with BM. In the conclusions, for the elliptical velocity field of the vibrations, the conditions to be observed in order to be able to direct the smallest vibrations towards the built up area are given.
Źródło:
Inżynieria Bezpieczeństwa Obiektów Antropogenicznych; 2023, 1; 53--60
2450-1859
2450-8721
Pojawia się w:
Inżynieria Bezpieczeństwa Obiektów Antropogenicznych
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An analytical-numerical method for calculating the stationary thermal field in electrical systems with elliptical cross-sections
Autorzy:
Gołębiowski, Jerzy
Zaręba, Marek
Powiązania:
https://bibliotekanauki.pl/articles/2128141.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
analytical-numerical methods of field theory
elliptical conductors
Poisson's equation
metody teorii pola analityczno-numeryczne
przewodniki eliptyczne
równanie Poissona
Opis:
In this article, an analytical-numerical approach to calculating a stationary thermal field in the elliptical region is presented. The eigenfunctions of the Laplace operator were determined analytically, whereas the coefficients of the eigenfunctions were obtained numerically. The cooling was modeled with 3rd kind (Hankel’s) boundary condition, where the total heat transfer coefficient was the sum of the convective and radiative components. The method was used to analyze the thermal field in an elliptical conductor and a dielectrically heated elliptical column. The basic parameters of these systems, i.e. their steady-state current rating and the maximum charge temperature, were determined. The results were verified using the finite element method and have been presented graphically.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2021, 69, 2; e136738, 1--6
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An analytical-numerical method for calculating the stationary thermal field in electrical systems with elliptical cross-sections
Autorzy:
Gołębiowski, Jerzy
Zaręba, Marek
Powiązania:
https://bibliotekanauki.pl/articles/2173609.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
analytical-numerical methods of field theory
elliptical conductors
Poisson's equation
metody teorii pola analityczno-numeryczne
przewodniki eliptyczne
równanie Poissona
Opis:
In this article, an analytical-numerical approach to calculating a stationary thermal field in the elliptical region is presented. The eigenfunctions of the Laplace operator were determined analytically, whereas the coefficients of the eigenfunctions were obtained numerically. The cooling was modeled with 3rd kind (Hankel’s) boundary condition, where the total heat transfer coefficient was the sum of the convective and radiative components. The method was used to analyze the thermal field in an elliptical conductor and a dielectrically heated elliptical column. The basic parameters of these systems, i.e. their steady-state current rating and the maximum charge temperature, were determined. The results were verified using the finite element method and have been presented graphically.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2021, 69, 2; art. no. e136738
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Blank shape optimization on deep drawing of a twin elliptical cup using the reduced basis technique method
Autorzy:
Golshani, M H
Jabbari, A.
Powiązania:
https://bibliotekanauki.pl/articles/957954.pdf
Data publikacji:
2015
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
deep drawing
twin elliptical cup
reduce basic technique
anisotropic
sheet
earring
Opis:
In this project thesis, initial blank shape optimization of a twin elliptical cup to reduce earring phenomenon in anisotropic sheet deep drawing process was studied .The purpose of this study is optimization of initial blank for reduction of the ears height value. The optimization process carried out using finite element method approach, which is coupled with Taguchi design of experiments and reduced basis technique methods. The deep drawing process was simulated in FEM software ABAQUS 6.12. The results of optimization show earring height and, in addition, a number of design variables and time of process can be reduced by using this methods. After optimization process with the proposed method, the maximum reduction of the earring height would be from 21.08 mm to 0.07 mm and also it could be reduced to 0 in some of the directions. The proposed optimization design in this article allows the designers to select the practical basis shapes. This leads to obtain better results at the end of the optimization process, to reduce design variables, and also to prevent repeating the optimization steps for indirect shapes.
Źródło:
Advances in Science and Technology. Research Journal; 2015, 9, 27; 72-77
2299-8624
Pojawia się w:
Advances in Science and Technology. Research Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Shooting Tests of Target Perforating Ability, Performed on Cast Concrete Cylinders
Autorzy:
Habera, Łukasz
Hebda, Kamil
Koślik, Piotr
Sałaciński, Tomasz
Powiązania:
https://bibliotekanauki.pl/articles/1062821.pdf
Data publikacji:
2020
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
shaped charge
axially-symmetric elliptical liner
hexogen
perforation channel
concrete
X-ray computer tomography
3D numerical visualisation
Opis:
In this paper, the first results of the applicability of shaped charges with a single liner, of a conical and of an axially-symmetric elliptical shape, are compared. The shaped charges were of an analogous type. The outer diameter and the height of the shaped charges were 39 and 42 mm, respectively. The mass of the explosive (flegmatized hexogen) in these charges was 27 g. The charges with the conical liner were commercially available. All liners used in these tests were made according to the same technology, as well as being of the same material, i.e. electrolytic copper. Two series of tests were carried out for shaped charges with the elliptical liner, i.e. 11 and 12 shots, with or without a distance plate between the shaped charge and the concrete shooting model (core), respectively. For comparison, 4 shots for each of these configurations were executed for commercial shaped charges with a conical liner. The distance plate was made of mild steel and its dimensions were 50×50×10 mm. All of the concrete cores used were uniform in the shape of a cylinder, with diameter 160 ±10 mm and height 1200 ±10 mm, and were prepared in a single-batch process. The tests were completed under outdoor conditions at ambient temperature. of 0.1 mm, were used to create 3D numerical visualisation of the perforation channels in the concrete cores created by the tested shaped charges. The 3D images allowed the depths to be measured, together with the volumes and degrees of uniformity of these channels. On the basis of these images, it was determined that the volume of the perforation channels created when using shaped charges with an elliptical liner were in the range 230-557 cm3, while the volumes created by commercial shaped charges were in the range 105-201 cm3. This is because charges with an elliptically shaped liner produced longer perforation channels than their analogues with conical liners. The tested shaped charges enclosing a single liner of an axially-symmetric elliptical shape assures better opening of a hydrocarbon reservoir in the downhole conditions of oil and gas wells, as compared to its analogous traditional form, with a conical liner.
Źródło:
Central European Journal of Energetic Materials; 2020, 17, 4; 584-599
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical modelling of shaped charges with an elliptical liner
Modelowanie numeryczne ładunków kumulacyjnych z wkładkami eliptycznymi
Autorzy:
Hebda, Kamil
Habera, Łukasz
Powiązania:
https://bibliotekanauki.pl/articles/1833993.pdf
Data publikacji:
2020
Wydawca:
Instytut Nafty i Gazu - Państwowy Instytut Badawczy
Tematy:
perforation
shaped charges
elliptical liner
numerical modelling
perforacja
ładunki kumulacyjne
wkładka eliptyczna
modelowanie numeryczne
Opis:
Artykuł został opracowany na podstawie wyników modelowania numerycznego ładunków kumulacyjnych z różnymi typami wkładek eliptycznych (trąbkowych). Zamodelowano trzy geometrie ładunków kumulacyjnych z wkładkami eliptycznymi, które porównano do modelu klasycznego ładunku kumulacyjnego z wkładką stożkową. Ładunki porównano pod względem maksymalnego ciśnienia podczas detonacji ładunku, prędkości strumienia kumulacyjnego, uzyskanej energii kinetycznej oraz długości strumienia kumulacyjnego po czasie 15 µs. Celem modelowania ładunków kumulacyjnych z wkładkami eliptycznymi była poprawa parametrów zabiegu perforacji w odwiertach naftowych. Wykonanie perforacji to kluczowy element, dzięki któremu możliwe jest zapoczątkowanie produkcji w danym złożu węglowodorów. Perforacja ma na celu wykonanie serii otworów prostopadłych do osi odwiertu, przebijających ścianki rur okładzinowych, cementu oraz skałę złożową, aby połączyć hydraulicznie otwór wiertniczy i złoże węglowodorów. Pożądane są jak najdłuższe otwory perforacyjne, które wraz ze wzrostem długości lepiej udostępniają złoże. Obecnie do perforacji wykorzystuje się ładunki osiowosymetryczne ze stożkowymi wkładkami kumulacyjnymi wykonanymi z proszków miedzi, które osiągają prędkość strumienia kumulacyjnego na poziomie 7000 m/s i penetrują do 1 m calizny skalnej przy sprzyjających warunkach. Zamodelowane ładunki kumulacyjne z wkładkami eliptycznymi osiągnęły znacznie lepsze wartości ciśnienia, prędkości maksymalnej, energii kinetycznej oraz długości po czasie dla strumienia kumulacyjnego w porównaniu do wyników modelowania strumienia powstałego z klasycznego ładunku kumulacyjnego. Należy jednak pamiętać, że aby potwierdzić skuteczność przebijania celów przez zamodelowane ładunki kumulacyjne, należałoby wykonać ich fizyczne modele i poddać je testom na poligonie doświadczalnym.
Źródło:
Nafta-Gaz; 2020, 76, 12; 929--933
0867-8871
Pojawia się w:
Nafta-Gaz
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mirror surface finishing of hardened die steel by high-Power ultrasonic elliptical vibration cutting
Autorzy:
Jung, H.
Shamoto, E.
Ueyama, T.
Hamada, S.
Xu, L.
Powiązania:
https://bibliotekanauki.pl/articles/100101.pdf
Data publikacji:
2016
Wydawca:
Wrocławska Rada Federacji Stowarzyszeń Naukowo-Technicznych
Tematy:
elliptical vibration cutting
mirror surface finishing
hardened steel
Opis:
Ultrasonic elliptical vibration cutting has recently been utilized in industry for finishing of various precision parts such as mirror surface finishing and precision micro machining of dies and molds. However, its application has been limited to high-cost ultra-precision machining, where depth of cut is typically in a range from a few micrometers to several tens of micrometers due to power limitation of the vibration device. To expand its application to low-cost mirror surface finishing with ordinary machining facilities, a high-power elliptical vibration device was developed in this research. The elliptical vibration cutting of hardened die steel was examined by applying the developed high-power elliptical vibration device with single crystalline diamond tools. Pick feed was kept to be 0.02 mm to obtain mirror quality surfaces, while depth of cut was increased up to 0.4 mm to verify performance of the high-power elliptical vibration cutting. By analyzing the experimental results, it was clarified that mirror surface finishing of the hardened die steel can be achieved at the large depth of cut with practically acceptable tool life.
Źródło:
Journal of Machine Engineering; 2016, 16, 1; 5-14
1895-7595
2391-8071
Pojawia się w:
Journal of Machine Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Interference in Multi-beam Antenna System of 5G Network
Autorzy:
Kelner, Jan M.
Ziółkowski, Cezary
Powiązania:
https://bibliotekanauki.pl/articles/226986.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
systems and networks
interference
multi-elliptical propagation model
multi-beam antenna system
simulation studies
massive MIMO
Opis:
Massive multiple-input-multiple-output (MIMO) and beamforming are key technologies, which significantly influence on increasing effectiveness of emerging fifth-generation (5G) wireless communication systems, especially mobile-cellular networks. In this case, the increasing effectiveness is understood mainly as the growth of network capacity resulting from better diversification of radio resources due to their spatial multiplexing in macro- and micro-cells. However, using the narrow beams in lieu of the hitherto used cell-sector brings occurring interference between the neighboring beams in the massive-MIMO antenna system, especially, when they utilize the same frequency channel. An analysis of this effect is the aim of this paper. In this case, it is based on simulation studies, where a multi-elliptical propagation model and standard 3GPP model are used. We present the impact of direction and width of the neighboring beams of 5G new radio gNodeB base station equipped with the multi-beam antenna system on the interference level between these beams. The simulations are carried out for line-of-sight (LOS) and non-LOS conditions of a typical urban environment.
Źródło:
International Journal of Electronics and Telecommunications; 2020, 66, 1; 17-23
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 43

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